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Question 1 of 177

1.

Administration of doxycycline hydrochloride caused an imbalance of the symbiotic intestinal microflora. Specify the kind of imbalance caused by the antibiotic therapy:

Explanation

Doxycycline is a tetracycline, broad spectrum antibiotic. Bacteriostatic; bind to 30s subunit of ribosome. Toxicity/adverse effect of tetracycline: GI distress, discoloration of teeth and inhibition of bone growth in children, fatal hepatotoxicity; photosensitivity (may cause severe sunburn when patients is exposed to sun or UV rays). Therefore avoid long stay in sun. It is contraindicated in pregnancy.

Administration of doxycycline hydrochloride (antibiotic) can cross react with the normal microflora in the intestine thereby causing dysbacteriosis (an imbalance in the normal microflora). All broad spectrum antibiotics can be associated with dysbacteriosis.

2.

A patient with signs of emotional lability that result in troubled sleep has been prescribed nitrazepam. Specify the sleep-inducing mechanism of this drug:

Explanation

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Nitrazepam is a hypnotic (tranquilizer) drug from the benzodiazepine family. Other drugs in this family include diazepam, lorazepam, triazolam, oxazepam etc. they facilitate GABAA action by increasing frequency of Cl- channel opening. They decrease rapid eye movement (REM) sleep.

3. A patient has arterial hypertension. What long-acting drug from the group of calcium channel blockers should be prescribed?

Explanation

Amlodipine is a calcium channel blocker (long acting); from the dihydropyridine family.

Atenolol is a β-blocker (cardioselective); Reserpine and Octadine are sympatholytics; Pyrroxanum is an adrenergic antagonist/α-adrenoblocker (non-selective α1 and α2).

4. In cancer patients who have been continuously receiving methotrexate, the target cells of tumor with time become insensitive to this drug. In this case, gene amplification of the following enzyme is observed:

Explanation

IMG_9914

Methotrexate is structurally related to folic acid and acts as an antagonist of that vitamin by inhibiting dihydrofolate reductase (in humans), which is the enzyme that converts folic acid to its active coenzyme form, tetrahydrofolic acid. Trimethoprim and pyrimethamine inhibit the same enzyme but in bacteria and protozoa respectively. This decreases dTMP, needed for DNA synthesis.

5.

A 30-year-old patient with a past history of virus B hepatitis complains of prolonged nosebleeds. What drug will be most efficient in remedying this condition?

Explanation

Vikasol (Menadioni natrii bisulfis) is a synthetic water soluble analogue of Vitamin K. it’s a coagulant. It participates in the formation of prothrombin. It promotes normalization of blood clotting. Indications include acute hepatitis, parenchymal and capillary bleeding, obstructive jaundice.

Dipiridamol – antiplatelet; platelet aggregating inhibitor (it’ll further exacerbate the nosebleed); Folic acid (Vit B9) is used to treat megaloblastic, macrocytic anemia; Fraxiparin – anticoagulant; Asparcam (panagin): source of K+ and Mg2+, prescribed for hypokalemia and hypomagnesemia. K+ and Mg2+ are not important for blood coagulation.

6. A 63-year-old male patient with bladder atony had been prescribed a medication, which he had been arbitrarily taking at a higher dose. The patient developed hyperhydration, salivation, diarrhea, muscle spasms. The prescribed drug relates to the following group:

Explanation

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Acetylcholine is a neurotransmitter. It increases salivary secretion and stimulates intestinal secretions and motility. It increases bronchial secretions, increases tone of detrusor urinae muscle, causing expulsion of urine, stimulates ciliary muscle contraction (accommodation). It increases exocrine gland secretions (e.g. lacrimal, salivary, gastric acid); gut peristalsis, bladder contraction, bronchoconstriction, papillary sphincter muscle contraction (miosis). Poisoning by cholinomimetics causes diarrhea, urination, miosis, bronchospasm, bradycardia, excitation of skeletal muscle and central nervous system, lacrimation, sweating and salivation. Cholinomimetics are cholinergic agonists which produce analogous effects of acetylcholine.

7.

A 47-year-old male patient developed intestinal colic against the background of essential hypertension. In this situation it would be most efficient to arrest the colic by using drugs of the following group:

Explanation

Only myotropic antispasmodics (muscle relaxants) can effectively manage both intestinal colic and essential hypertension. Because sympathomimetics and adrenomimetics will exacerbate hypertension the more. Anticholinesterase agents and M-cholinomimetics will ↑acetylcholine effects in neuromuscular junction → ↑arteriolar smooth muscle tone → exacerbate hypertension. But the myotropic antispasmodics can ↓ muscle tone in intestinal smooth muscle (thereby relieving intestinal colic) and also ↓ arteriolar smooth muscle tone (thereby relieving essential hypertension).

8. A patient complains of photoreception disorder and frequent acute viral diseases. He has been prescribed a vitamin that affects photoreception processes by producing rhodopsin, the photosensitive pigment. What vitamin is it?

Explanation

Rhodopsin or visual purple is the photosensitive pigment of rod cells. It is made up of a protein called opsin and a chromophore. Opsin present in rhodopsin is known as scotopsin. Chromophore is a chemical substance that develops colour in the cell. Chromophore present in the rod cells is called retinal. Retinal is the aldehyde of vitamin A or retinol. Vitamin A is the name given to a group of related compounds that include retinol (vitamin A alcohol); retinal (vitamin A aldehyde) and retinoic acid (vitamin A acid). Rod cells are responsible for dim light vision or night vision or scotopic vision.

9. A patient with acne has been prescribed doxycycline hydrochloride. What recommendations should be given to the patient, while he is taking this drug?

Explanation

Doxycycline is a tetracycline, broad spectrum antibiotic. Bacteriostatic; bind to 30s subunit of ribosome. Toxicity/adverse effect of tetracycline: GI distress, discoloration of teeth and inhibition of bone growth in children, fatal hepatotoxicity; photosensitivity (may cause severe sunburn when patients is exposed to sun or UV rays). Therefore avoid long stay in sun. It is contraindicated in pregnancy. All broad spectrum antibiotics can be associated with dysbacteriosis.
10. A 26-year-old female patient with bronchitis has been administered a broad spectrum antibiotic as a causal treatment drug. Specify this drug:

Explanation

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Doxycycline is a tetracycline, broad spectrum antibiotic. Bacteriostatic; bind to 30s subunit of ribosome.

image

All other options are not antibiotics.

Toxicity/adverse effect of tetracycline: GI distress, discoloration of teeth and inhibition of bone growth in children, fatal hepatotoxicity; photosensitivity (may cause severe sunburn when patients is exposed to sun or UV rays). Therefore avoid long stay in sun. It is contraindicated in pregnancy. All broad spectrum antibiotics can be associated with dysbacteriosis.

11. Symptoms of pellagra (vitamin PP deficiency) is particularly pronounced in patients with low protein diet, because nicotinamide precursor in humans is one of the essential amino acids, namely:

Explanation

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Vit. B3 (Niacin, PP): coenzyme forms NAD+, NADP+ is derived from tryptophan. Synthesis requires Vit. B2 and B6.

12. A 68-year-old patient consults a cardiologist, complaining of high arterial blood pressure, pain in the heart region, intermittent pulse. Prescribe the β1-adrenoreceptor blocker for the treatment of the described pathology:

Explanation

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β1-adrenoblocker (cardioselective) – Metoprolol: blocks β1-adrenoreceptors of the heart. Fenoterol β2-adrenomimetics (short-acting 4-6hrs). Benzylpenicillin – short acting penicillin (β-lactam antibiotic). Nootropil – Nootropic. Morphine hydrochloride – Narcotic analgesic.

13.

A patient is diagnosed with acute morphine hydrochloride intoxication. Prescribe an oxidizing agent for gastric lavage:

Explanation

Potassium permanganate: KMnO4 →MnO2 + O2. MnO2 has astringent action. O2  oxidizes proteins in microbes, deodorizing action, antidote action. 0.1% - 100ml for gastric lavage. Chloramines and chlorhexidine bigluconate – nonorganic antiseptic and disinfectant  → chlorine containing (halogens) for treatment of wounds and processing of surgeon’s hands. Sulfocamphocainum – respiratory stimulant.

14.

A 35-year-old female patient has been hospitalised with acute intoxication caused by salts of high-density metals (lead, most probably). As a part of complex therapy the antidote that contains two active sulfhydric groups has been prescribed. Specify this antidote:

Explanation

Dimercaprol (unithiol, British anti-lewisite) is used to chelate mercury, bismuth, arsenic and in combination with edentate calcium disodium to treat lead intoxication. It contains two sulfuhydryl (SH-) groups and forms two bonds with metal ions. Administered intramuscularly.

Mannitol – osmotic diuretic; Nalorphine hydrochloride – antidote, blocks opoid receptors and replace opoids from binding with them. Metamizole: analgesic, non-opoid drug. Calcium chloride – Calcium preparation, coagulant with systemic action.

15.

A 60-year-old male patient has type II diabetes. A doctor has prescribed him synthetic hypoglycemic long-acting drug that is sulfonylurea derivative. What drug is it?

Explanation

Sulfonylurea are insulin secretagogues because they promote insulin release from the β-cells of the pancreas. The primary drugs used today are the 2nd generation drugs – glibenclamide, glipizide, glimepiride etc. These agents are useful in the treatment of patients who have type 2 diabetes mellitus and cannot be managed by diet alone. Metformin is the only currently available biguanide; its classed as an insulin sensitizer. Acarbose – α glucosidase inhibitor. Butamide (tolbutamide) is also a sulfonylurea but is older and glibenclamide is more potent and used much more commonly. Actrapid (soluble insulin) is fast acting but not a sulfonylurea.

16.

A patient has been given atropine sulfate for rapid relief of spastic colon symptoms. The use of this drug is contraindicated during the following disease:

Explanation

Glaucoma: increased intraocular eye pressure. Atropine sulfate (M-cholinoblocker) blocks the acetylcholine response of the ciliary muscle of the eye and of the circular smooth muscles of the iris, producing cycloplegia and mydriasis; it may increase intraocular pressure especially in patients with narrow-angle glaucoma. At low doses, it decreases cardiac rate (bradycardia). Arterial blood pressure is unaffected by atropine but at toxic levels, it will dilate the cutaneous vasculature. It is not effective in promoting healing of peptic ulcer. It can also relieve bronchial asthma. It is contraindicated because its going to further increase intraocular pressure.

17.

A patient who had been taking diclofenac sodium for arthritis of mandibular joint developed an acute condition of gastric ulcer. Such side effect of this medicine is caused by inhibition of the following enzyme:

Explanation

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Diclofenac-natrium(sodium) is a non-selective inhibitor of COX-1 and COX-2. Cyclooxygenase (COX) converts arachidonic acid into the endoperoxide precursors of prostaglandin. COX-1 is present in non-inflammatory cells (normal body tissues); COX-2 is present in lymphocytes, polymorphonuclear cells and other inflammatory cells. Side effects: Gastro-Intestinal (GI) symptoms – bleeding, ulceration and perforation. Because COX-1 is used to produce mediators that help to protect gastric mucosa, whenever COX inhibitors are used they produce these side effects.

18.

A 55-year-old male had been delivered to the resuscitation unit unconscious. Relatives reported him to have mistakenly drunk an alcoholic solution of unknown origin. On examination the patient was diagnosed with methanol intoxication. What antidote should be used in this case?

Explanation

imageFullSizeRender (5) The specific antidote for methanol or ethylene glycol poisoning/intoxication is ethanol or fomepizole by inhibiting alcohol dehydrogenase which delays the methanol metabolism until methanol is eliminated; Methanol is relatively nontoxic, but is metabolized by alcohol dehydrogenase to toxic metabolites.
19.

An   8-week-pregnant   woman with acute respiratory disease and temperature rise up to 39, 0oC has called in a doctor. The doctor insisted on her avoiding taking paracetamol, because in this period of pregnancy there is a risk of its:

Explanation

There is structural damage (i.e. affecting organ formation) in a 1st trimester exposure and functional damage (i.e. affecting organ maturation and/or function) in 2nd and 3rd trimester exposures to paracetamol. It is teratogenic because it is able to disturb the growth and development of an embryo or fetus.

20. A pneumonia patient has been administered acetylcysteine as a part of complex therapy. What principle of therapy has been taken into consideration when applying this drug?

Explanation

Acetylcysteine is an expectorant (mucolytic), which ↑bronchial secretion or reduce its viscosity, facilitating its removal by coughing; they loosen cough which becomes less tiring and more productive. This drugs treats the pathogenesis/development of the disease and not its cause (etiology-etiotropic) or symptoms (symptomatic).

21. A patient with chronic heart failure with edema has increased level of blood aldosterone. What diuretic would be most effective in this case?

Explanation

IMG_9896

K+ sparing diuretics:

  - aldosterone antagonist: spironolactone, eplerenone

  - inhibit Na+ reabsorption: triamterene

     Carbonic anhydrase inhibitor: acetazolamide; Thiazide diuretics: hydrochlorthiazide; Loop diuretics: furosemide

22. What drug will be most appropriate for the patient who has chronic gastritis with increased secretion?

Explanation

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Pirenzepine (selective M1-cholinoblocker) – decrease gastric secretion. Pancreatine (polyenzyme drug) – increase gastric secretion. Aprotinin (contrycal, gordox) – antitrypsin; antiprotease. Chlorphentermine (desopimonum): appetite suppressant, stimulating CNS.

23.

A child was born asphyxiated. What drug must be administered to the newborn to stimulate breathing?

Explanation

Analeptics (aethimizolum): drugs which act upon the CNS general functions, but stimulate mainly medulla oblongata (respiratory, cardiovascular centers). Aethimizolum acts on the medulla with a direct action.

Aethimizolum also activates the adrenocorticotropic pituitary function which increase cortisol level → ↑production of surfactant. All other options are analeptics but they are only used in the absence of aethimizolum in case of children born with asphyxia.

Lobeline (N-cholinomimetic) can also act as an analeptic but with a reflexive type of action and does not influence the medulla directly. Prazosin (α1-receptor blocker); Atropine (M-cholinoblocker); Proserin/Neostigmine (cholinomimetic).

24.

A patient complaining of rapid pulse, dyspnea and bluish color of mucosa has been admitted to the cardiological department. The objective symptoms are as follows: edema of lower extremities, ascites. Which of the given medicines should be prescribed for intravenous administration to improve the patient’s general state?

Explanation

The symptoms describe cardiac insufficiency. Cardiac glycoside is the most appropriate in this case. Cardiac glycosides are glycosidic drugs of plant origin having cardiac inotropic property, increase myocardial contractility and output. Corglyconum is short acting for acute cardiac insufficiency and administered intravenously.

Digitoxin is long-acting but basically administered orally and used mainly for chronic heart failure (also digoxin).

Cordiamin – analeptic; Adrenaline is commonly used in shocks and coma; Drotaverine – phosphodiesterase 4 inhibitor, antispasmodic (relaxant). Phosphodiesterase 3 inhibitor (nonglycoside cardiotonic)

25.

A patient takes cholagogues. What other process besides biliary excretion will be stimulated?

Explanation

Cholagolics are bile expelling drugs. Their pharmacological effects include: promotes bile excretion and emulsification of fats; absorption of fat and lipid soluble vitamins in intestine, enhance intestinal motor function (intestinal motility).

26. A patient with homogentisuria has signs of arthritis, ochronosis. In this case, the pain in the joints is associated with the deposition of:

Explanation

krushkrok No21 (2014)image

Ochronosis (Alkaptonuria): congenital deficiency of homogentisate oxidase (homogentisic acid oxidase) in the degradative pathway of tyrosine to Fumarate → pigment-forming homogentisic acid accumulates (homogentisuria) in tissues. Autosomal recessive. Usually benign. Urine turns black on prolonged exposure to air. May have debilitating arthralgias (homogentisic acid toxic to cartilage).

27. A child patient has dry cough. What non-narcotic antitussive drug will relieve the patient’s condition?

Explanation

Narcotic – Opoid. Tussive – Cough.

Glaucine hydrochloride is the only antitussive centrally acting but non-opoid (non-narcotic).

Codeine phosphate and Morphine hydrochloride - antitussive centrally acting but opoid.

28.

An patient with insomnia induced by allergic rash and itch has been prescribed the drug that has antihistamine and hypnotic effect. Specify this drug:

Explanation

Benadryl (Diphenhydramine, Dimedrol): Antihistamine (1st generation) – H1 receptor blocker. Has sedative, hypnotic and ganglioblocking effects. Loratadine (2nd generation) – also  an antihistamine but has a weak sedative, hypnotic effect. Prednisolone, Acetylsalicylic acid and Analgin are not antihistamines.

29.

During local anesthetization the patient has gone into anaphylactic shock. What drug must be administered to the patient?

Explanation

* Epinephrine/Adrenaline hydrochloride: is an α-β-adrenergic agonists (adrenomimetics), direct acting. Uses: Anaphylactic shock, hypoglycemic coma…

* Diazepam: Tranquilizer (Benzodiazepine). Uses: anxiety, status epilepticus, night terrors.

* Atropine sulphate: M-cholinoblocker. Uses: eye traumas, GI diseases with ↑acidity.

* Propanolol: β-blocker. Uses: hypertension, Ischemic heart disease.

* Nitroglycerine: Organic nitrates. Uses: angina attack

30.

Ascarid eggs have been detected during stool analysis. What drug should be prescribed?

Explanation

Mebendazole – antihelminthic drug (chemotherapy of nematodes – roundworms). Ascarid eggs are gotten from Ascaris lumbricoides. Other drugs in this group are levamisolum, piperazinum,pyrantel. Nystatin is an antifungal; Chloramphenicol, Tetracycline, Furozolidone are antibiotics.

31.

 A patient with continuous bronchopneumonia was admitted to the therapeutic department. Antibiotic therapy didn’t give much effect. What medication for improvement of immune state should be added to the complex treatment of this patient?

Explanation

Thymalin is an immunostimulator, it’s the complex of polypeptides fractions of thymus gland of horned cattle. It is a drug of first generation. It stimulate cells immune reactions, restore T lymphocytes quantity and function, correlation of T and B lymphocytes, their subpopulations and increase native killers’ activity, intensify phagocytosis and lymphokines production. It is used in complex therapy of immune deficiency diseases and trophic ulcers.

32.

To anaesthetize the surgical treatment of burn surface, a patient was intravenously injected a medication for short-acting narcosis. 1 minute later the patient being under anesthesia showed increased blood pressure, tachycardia, increased tone of skeletal muscles; reflexes remained. After recovering from anesthesia the patient had disorientation and visual hallucinations. What medication was the patient injected?

Explanation

Ketamin is an intravenous anesthesia. It is an antagonist of glutamic acid, blocking the actions of this excitatory transmitter. The drug is a cardiovascular stimulant and this action may lead to an increase in intracranial pressure. Reactions such as disorientation, excitation and hallucinations can occur during recovery from ketamin anesthesia. It has no effect on laryngeal reflexes. Skeletal muscle tone, heart rate, arterial blood pressure and cerebrospinal fluid pressure can be increased by ketamin.

33.

A 45-year-old woman suffers from seasonal allergic rhinitis caused by the ambrosia blossoming. What medicine from the stabilizer of the adipose cells group can be used for prevention of this disease?

Explanation

Ketotifen and cromolyn sodium are membrane stabilizers. Ketotifen stabilize basophils membranes and possesses antihistamine (antiallergic) and sedative effects.
34. Analeptical remedy of reflective type from the H-cholinomimetics group was given to the patient for restoration of breathing after poisoning with carbon monoxide. What medicine was prescribed to the patient?

Explanation

Lobeline hydrochloride is a N-cholinergic agonists (N-cholinomimetics). It stimulates N-cholinoreceptors located in the CNS, carotid glomerulus, sympathetic and parasympathetic ganglia and adrenal medulla. They are used as respiratory stimulants (analeptics with reflex action) in respiratory arrests.

Atropine sulphate: M-cholinergic antagonist (M-cholinoblocker)

Adrenaline hydrochloride: adrenergic agonist (adrenomimetic)

Mesaton: α-adrenergic agonist (α-adrenomimetic)

Pentamin: ganglioblocker

35.

A 36 y.o. man has a craniocerebral trauma. Objectively: diminished breath sounds, thready pulse, no reflexes. What way of pyracetam introduction will be the most appropriate in this case?

Explanation

Pyracetam (Nootropil) is a nootropic. Nootropic drugs are drugs which improve cerebral blood flow and optimize energetic metabolism in neurons, increase brain stability in hypoxia, stimulate higher cortical function, memory and education processes. It is administered 20% - 5ml of solution. Craniocerebral trauma is an emergency case; so for fast onset of action, it is administered intravenously. Although, it can also be administered orally or intramuscularly.

36.

A patient suffers from severe postoperative pseudomonadous infection. What of the following antibiotics should be administered in this case?

Explanation

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Aminoglycosides (streptomycini sulfas – 1st generation; Gentamycini sulfas – 2nd generation; Amikacin sulfate – 3rd generation; Arbekacin sulfate - 4th generation). They are protein synthesis inhibitors (antibiotics) and bactericidal. They cause irreversible inhibition of initiation complex through binding of the 30S ribosomal subunit, can also cause misreading of mRNA and also block translocation.

image

Therapeutic uses include: Pneumonia, chronic urinary tract infections, Tularemia and infections due to Pseudomonas aeruginosa.

37.

A patient ill with collagenesis has been taking prednisolone for a long time. Hypokaliemia development caused spastic pain of skeletal muscles. What medication should be used in order to correct potassium exchange?

Explanation

Panangin is an antidote; a potassium preparation. It is indicated in hypokalemia. It is used to replace potassium concentration in the body. It can also be used as an antiarrhythmic drug.

38. A 60-year-old patient was admitted to the surgical department because of infection caused by blue pus bacillus (Pseudomonas aeruginosa) which is sensitive to penicillin antibiotics. Indicate which of the given penicillins has marked activity to the Pseudomonas aeruginosa?

Explanation

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Antipseudomonas penicillins: carbenicillin, ticarcillin, piperacillin – these drugs have activity against several gram negative rods, including Pseudomonas, enterobacter and in some cases Klebsiella species. Carbenicillin-disodium is acid-stable and can be administered orally.

39. A patient with II stage hypertension has been taking one of hypotensive medications for the purpose of treatment. After a time arterial pressure decreased, but the patient started complaining of flaccidity, sleepiness, indifference. A bit later he felt stomach pain. He was diagnosed with ulcer. What hypotensive medication has the patient been taking?

Explanation

Reserpine, a plant alkaloid is a sympatholytic; it blocks the Mg2+/adenosine triphosphate-dependent transport of biogenic amines, norepinephrine, dopamine and serotonin from the cytoplasm into storage vesicles in the adrenergic nerves of all body tissues. This causes the ultimate depletion of biogenic amines. Sympathetic function in general is impaired because of decreased release of norepinephrine (↓Arterial pressure). But studies have shown that an appropriate dose of reserpine provokes an increase in output of HCl by the stomach, leading hyperacidity in stomach which is ulcerogenic. Reports of peptic ulceration in individuals receiving reserpine and of increased gastric secretion upon administration of this drug, have engendered the suspicion that reserpine is a significant ulcerogenic agent.

40. A patient with acute  morphine poisoning  was delivered to a hospital.  What specific narcotic  antagonist should be chosen in this case?

Explanation

Acute poisoning with narcotic analgesics (e.g. morphine) is characterized by sleep or unconsciousness, normal or increased reflexes, normal muscle tone, miosis, bradycardia, cheyne-stokes breath, the retention of urine, a spasm of intestine and bowel. This condition can be treated with:

·        Stomach lavage with 0.5% solution of potassium permanganate.

·        Intravenous injection of Naloxone (naloxone is an antagonist of narcotic analgesic).

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·        Atropine; for decrease in the vagal action of morphine.

41. A   7   year   old   child   is   ill   with bronchitis.   It  is necessary  to  administer him   an   antibacterial  drug.   What   drug of fluoroquinolone group is CONTRA- INDICATED at this age?

Explanation

Fluoroquinolones: ciprofloxacin, norfloxacin, levofloxacin, ofloxacin, moxifloxacin. They are all antibiotics. They inhibit prokaryotic enzymes topoisomerase II (DNA gyrase) and topoisomerase IV.

image

They are bactericidal and must not be taken with antacids. It is contraindicated in pregnant women, nursing mothers and children

Fluoroquinolones hurt attachments to your Bones.

42. A patient with frequent attacks  of stenocardia  was  prescribed  sustak-forte to be taken  one tablet  twice a day. At first the effect was positive  but on the second day  stenocardia attacks   resumed.  What can explain  inefficiency of the prescribed drug?

Explanation

Idiosyncrasy and allergic reaction is as a result of organism’s increased sensitivity to the drugs. It’s a complication of pharmacological therapy (adverse reactions). Tolerance and Tachyphylaxis are effects of repeated doses.

* Idiosyncrasy is genetically conditioned perverse organism’s response to drugs (e.g. inefficiency, lack of enzymes participating in drug metabolism). Genetic deficiency of glucose 6-phosphate dehydrogenase (hereditary enzymopathy). This enzyme is needed for proper functioning of glutathione (an antioxidant) to prevent the oxidative effect of antimalarial drugs on the RBCs.

* Allergic reactions results from antibody production against some drugs.

* Tachyphylaxis is quick weakening of the effect, sometimes may occur after first drug introduction (usually connected with substrate exhaustion).

* Tolerance (habituation): is increasing of the effects in repeated doses resulting from decreasing of absorption, speed-up of the biotransformation or excretion, or decreasing of the receptors sensitivity.

43. A  45-year-old  patient suffers  from neurosis characterized by irritability, sleeplessness,   motiveless   anxiety.   What drug would eliminate all the symptoms?

Explanation

All of the benzodiazepines used to treat anxiety (tranquilizers) have some sedative properties and some can produce hypnosis (artificially produced sleep) at higher doses. Their effects have been shown to be mediated by the α1-GABAA receptors. image Benzodiazepines are the most widely used anxiolytic drugs e.g. Diazepam, lorazepam, nitrazepam, clonazepam etc. They are also used to treat neurosis.
44. A patient who has been taking a drug for  a long  time  cannot  abruptly stop  its use, because  this may lead to psychic and somatic dysfunctions. Name the syndrome of different disorders caused by a drug withdrawal:

Explanation

Abstinence: apart from drugs that are usually recognized as producing dependence, sudden interruption of therapy with certain other drugs also results in adverse consequences, mostly in the form of worsening of the clinical condition for which the drug was being used e.g. Acute adrenal insufficiency may be precipitated by abrupt cessation of corticosteroid therapy; frequency of seizures may increase on sudden withdrawal of an antiepileptic etc. These manifestations are also due to adaptive changes and can be minimized by gradual withdrawal.

45. Before   tooth   extraction  a  patient was  advised  to  take  a  certain   drug  for hemorrhage prevention. What drug was advised?

Explanation

Vikasol (Menadioni natrii bisulfis) is a synthetic water soluble analogue of Vitamin K.

image

It’s a coagulant i.e. it prevents hemorrhage (bleeding). It participates in the formation of prothrombin. It promotes normalization of blood clotting. Indications include acute hepatitis, parenchymal and capillary bleeding, obstructive jaundice.

46.

In clinical practice  tuberculosis is treated with  izoniazid  preparation - that is an  antivitamin able  to  penetrate into the  tuberculosis bacillus.  Tuberculostatic effect  is induced  by the  interference with replication processes  and oxidation-reduction reactions due to the buildup  of pseudo-coenzyme:

 

Explanation

Isoniazid is the hydrazide of isonicotinic acid and is a pyridine. Pyridine occurs in many important compounds including  azines and the Vitamins Niacin(B3, NAD) and Pyridoxine(B6). Therefore, isoniazid can be interfered with Vit.B3,B6 and even B1 metabolism by competing with them.

Isoniazid is a first line antituberculosis drug that inhibits the synthesis of mycolic acid. Vit B6 is needed for the transformation of tryptophan to Vit.B3.

Adverse reaction of Isoniazid: peripheral neuritis, optic neuritis, hepatitis and idiosyncratic hepatotoxicity.
47. A patient suffering from chronic bronchitis    takes   a   synthetic   mucolytic drug that  facilitates  the  sputum  thinning. What drug is it?

Explanation

Acetylcysteine is a synthetic mucolytic (expectorant). It has sulfhydryl group that tear disulfide connections, helps mucosa expelling and reduces the viscosity of mucus. Besides this acetylcysteine is an antioxidant and cardioprotector. It increases bronchial secretion or reduce its viscosity (sputum thinning), facilitating its removal by coughing, they are believed to “loosen” cough which becomes less tiring and more productive.

48. A  student  came   to  see  a  doctor and  asked  to  administer him  a drug  for treatment of allergic rhinitis that occurs in the period  of linden flowering. What drug may be used?

Explanation

Loratidine : Antihistamine (antiallergic) block H1-histamine receptors as well as adrenergic, cholinergic & serotonin-binding recpetors. They do not influence the formation or release of histamine, but rather they competitively block the receptor-mediated response of target tissue.                                                                                           
49. A patient with drug intoxication presented with the dryness of oral mucous membrane  and   mydriatic   pupils.   Such action  of this drug  is associated  with the following effect:

Explanation

Muscarinic receptors belong to the class of G protein-coupled receptors. These receptors, in addition to binding Acetylcholine, it also recognizes muscarine – an alkaloid that is present in certain poisonous mushrooms. Muscarinic effects include miosis, spasm of accommodation, increasing of lacrimal, salivary, gastrointestinal, bronchial and sweat glands secretion, increase of smooth muscle tonus of internal organs, bradycardia, decreased arterial pressure.

image

Block of M-cholinoreceptor or sympathetic nervous system will produce the opposite effects as described in the question.

50. An   elderly   female   patient  suffers from the type 2 diabetes mellitus accompanied by  obesity,  atherosclerosis, coronary artery disease. Basal hyperinsulinemia  is  also  present.  What treatment would be the most appropriate?

Explanation

Sulfonylurea are insulin secretagogues because they promote insulin release from the β-cells of the pancreas. The primary drugs used today are the 2nd generation drugs – glibenclamide, glipizide, glimepiride etc. These agents are useful in the treatment of patients who have type 2 diabetes mellitus and cannot be managed by diet alone.  Glibenclamide is much more potent and used commonly. 

51.

A patient suffering from coronary artery disease had taken a certain drug many times a day in order to arrest   stenocardia  attacks. Overdose of this drug finally caused intoxication. Objectively: cyanotic skin and mucous membranes, dramatic fall in the  arterial pressure, tachycardia, respiration inhibition. Blood  has increased concentration of methemoglobin. The drug the patient had taken  relates to the following group:

Explanation

The most common drug used in treating stenocardia is organic nitrates (nitroglycerine). High doses of organic nitrates can cause postural hypotension, facial flushing, tachycardia and headache. Overdose can increase nitrates concentration in blood leading to the formation of methemoglobin with a decreased ability to bind O2. This results in shortness of breath (respiratory inhibition), cyanosis, mental status changes, fatigue etc.

52. Continuous use of a certain  drug may cause  osteoporosis, erosions  of  stomach mucosa,  hypokaliemia, retention of sodium and water  in the organism,  decreased concentration of  corticotropin  in  blood. What drug is it?

Explanation

Some commonly observed effects of long-term corticosteroid therapy includes the following:

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Osteoporosis is a common adverse effect of long-term corticosteroid therapy, due to the ability of glucocorticoids (prednisolone) to suppress intestinal Ca2+ absorption, inhibit bone formation and decrease sex hormone synthesis. Other adverse effects include peptic ulcer (erosions of stomach mucosa), hypokalemia, emotional disturbances and the classic cushing-like syndrome (i.e. redistribution of body fat, puffy face, increased body hair growth, acne, insomnia and increased appetite) are observed when excess corticosteroids are present. Excess corticosteroid results in decreased corticotrophin (adrenocorticotropic hormone) through the negative feedback mechanism.

53.

To  prevent  the  transplant  rejection after   organ   transplantation  it  is  required   to  administer  hormonotherapy  for the purpose of immunosuppression. What hormones are used for this purpose?

Explanation

Glucocorticoids have immunosuppressive effects, anti-inflammatory effects, anti-shock, anti-allergic and anti-toxic effects. Immunosuppressive effects: glucocorticoids inhibit some of the mechanisms involved in cell-mediated immunologic functions, especially those dependent on lymphocytes. These agents are actively lymphotoxic and are important in the treatment of hematologic cancers. The drugs do not interfere with the development of normal acquired immunity but delay rejection reactions in patients with organ transplants. This immunosuppressive effect makes the patient susceptible to other infectious diseases (e.g. chronic tonsillitis).

54. A patient with hip fracture was prescribed  a  narcotic   analgetic.   Its anesthetic action is determined by interaction with the following receptors:

Explanation

Opoids (narcotic analgetic) are natural or synthetic compounds that produce morphine-like effects. All drugs in this category act by binding to specific opoid receptors in the CNS to produce effects that mimic the action of endogenous peptide neurotransmitters (e.g. endorphins, enkephalins and dynorphins). Although the opoids have a broad range of effects, their primary use is to relieve intense pain, whether that pain is from surgery or a result of injury or disease such as cancer.

55. A patient who had myocardial infarction was administered 75 mg of acetylsalicinic acid a day. What is the purpose of this administration?

Explanation

image Acetylsalicyclic acid (Aspirin) is an NSAID. Cycloxygenase, the enzyme which converts arachidonic acid into the endoperoxide precursors of prostaglandin, has at least two different  isoforms: COX-1 & COX-2. COX-1 is primarily expressed in non-inflammatory cells whereas COX-2 is expressed in activated lymphocytes, polymorphonuclear cells and other inflammatory cells. Acetylsalicyclic acid and the other non-selective NSAIDs inhibit both cyclooxygenase isoforms & thereby decrease prostaglandin & thromboxane synthesis (disaggregating effect) throughout the body.
56.

A  patient has  herpetic rash.  What medication should be administered?

Explanation

Acyclovir is an antiviral drug for herpes and cytomegalovirus infections. The drug is indicated for primary and recurrent mucocutaneous herpes simplex infections in immunocompromised patients. It is also useful in herpes genitalis infections.

57. A 50 year old man who was referred to  the  hospital  for  treatment of cervical lymphadenitis underwent test  for individual  sensitivity  to  penicillin.  30 seconds after  he  went  hot  all over,  AP  dropped down  to  0  mm  Hg  that  led  to  cardiac arrest.  Resuscitation was unsuccessful. Autopsy  results:  acute   venous   plethora of internal organs; histological  examination of skin (from the site of injection) revealed  degranulation of mast  cells (tissue  basophils). Degranulation  was  also revealed  in myocardium and lungs. What type of hypersensitivity reaction is it?

Explanation

Type I Hypersensitivity reaction (HSR); anaphylactic and atopic: free antigen cross-links IgE on presensitized (i.e. exposed to the antigen before) mast cells and basophils, triggering immediate release of vasoactive amines that act at postcapillary venules (i.e. histamine). Reaction develops rapidly after antigen exposure because of preformed antibody from first exposure. IgE is the main immunoglobulin involved in type I HSR. Type I: uses IgE and IgG4

Type I (Immediate, Anaphylaxis, Reagin): IgE (immunoglobulin E)-dependent activation of mast cells/basophils, usually accompanied by eosinophilia e.g. urticaria (hives), hay fever, asthma (wheezing), rhinitis and conjunctivitis (stuffy nose and itchy eyes; usually seasonal)

58. A patient with chronic cardiac insufficiency  has  been  taking   foxglove  (Digitalis)  preparations for  a  long  time.  Due to  the  violation   of  intake   schedule   the woman   got   symptoms   of   intoxication.  These symptoms result from:

Explanation

Effect of repeated doses include: accumulation, tolerance (habituation), tachyphylaxis and drug dependence.

            Accumulation is enhancing of the effects in repeated doses that leads to the appearance of toxic effects. 2 types are distinguished:

·        Material accumulation: is accumulation of drug in the manner of bindings with proteins, phospholipids etc.

·        Functional accumulation is accumulation of the drug effect, in spite of its elimination.

The cardiac glycosides are often called digitalis or digitalis glycosides, because most of the drugs come from the digitalis (foxglove) plant. Non-polar glycosides (digitoxin) are fully absorbed and firmly connected with proteins – plasma protein binding 95%. These drugs are accumulated.

59. Burned skin surface  was treated with a certain preparation. Its antiseptic properties are provided  by atomic oxygen that is formed  in presence of organic substances.  What  preparation was applied?r

Explanation

Potassium permanganate is a non-organic antiseptic and disinfectant. Its an oxidizing agent liberating oxygen, which oxidizes bacterial protoplasm. KMnO4 → MnO2 + O2.

MnO – astringent action; O2- oxidizing proteins in microbes, deodorizing action, antidote action.

Potassium permanganate is used in disinfections of impaired skin and mucous areas, irrigation of pus wounds.

·        Irrigation of purulent wounds (0.01 – 0.5% solution)

·        Gargling and mouthwash in diseases of throat and oral cavity (0.01 – 0.1% solution)

·        Syringing in gynecology and urology (0.01 – 0.1% solution)

·        Processing of burns (2 – 5% solution)

·        Lavage of stomach in acute poisoning with morphine, alcohol (0.1% solution)

Furacillin: organic antiseptic and disinfectant → furan derivative

Chlorhexidine bigluconate: nonorganic antiseptic and disinfectant → halogen → chlorine containing

Alcoholic iodine solution: nonorganic antiseptic and disinfectant → halogen → iodine containing

Sodium hydrocarbonate: drug for transfusion therapy → drug for correction of acidosis.

60. An  alcoholic  woman  has born  a girl with mental  and  physical  developmental lag. Doctors diagnosed the girl with fetal alcohol syndrome. What effect is the cause of the girl’s state?

Explanation

Intoxication with drugs leads to:

·        Disturbances in organs and systems functions: neurotoxic, hepatotoxic, nephrotoxic, hematotoxic, ulcerogenous – ulcers formation in GIT.

·        Teratogenic: ability to cause fetal malformation (in the first trimester of pregnancy i.e. till 12 weeks.

·        Embryo and fetotoxic: ability to make a toxic influence on embryo and fetus correspondingly, causing disturbance down to death (after 12 weeks).

·        Mutagenic: ability to impact on a genetic level causing mutations in several generations.

·        Blastogenic: ability to cause neoplasms both benign and malignant (carcinogenic).

Mental and physical development lag; fetal alcohol syndrome are fetal malformations.

61.

A patient in a transplantation centre underwent heart  transplantation. The organ  was  taken  from  a  donor  who  died in a road  accident.  Foreign  heart  can be  rejected as  a  result  of  development of transplantation immunity.  It is usually prevented by means of:

Explanation

The introduction of an allograft (that is, the graft of an organ or tissue from one individual to another who is not genetically identical) can elicit a damaging immune response, causing rejection of the transplanted tissue. Drugs (immunosuppressors) are now available that more selectively inhibit rejection of transplanted tissues while preventing the patient from becoming immunologically compromised. The principal approach to immunosuppressive therapy is to alter lymphocyte function using drugs or antibodies against immune proteins. Immunosuppressive therapy is also used in the treatment of autoimmune diseases e.g. adrenocorticoids (prednisolone).

62.

A  patient suffers  from  chronic  left-ventricular insufficiency. What medication should be administered?

Explanation

 Cardiac glycoside is the most appropriate in this case. Cardiac glycosides are glycosidic drugs of plant origin having cardiac inotropic property, increase myocardial contractility and output.

Corglyconum is short acting for acute cardiac insufficiency and administered intravenously.

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Digitoxin is long-acting but basically administered orally and used mainly for chronic heart failure (also digoxin).

63. A patient complained about  muscle rigidity, constrained motions, constant tremor of arms. On the grounds of examination his disease was diagnosed  as Parkinson’s disease. What drug should be administered?

Explanation

image

Levodopa is a metabolic precursor of dopamine. It restores dopaminergic neurotransmission in the corpus striatum by enhancing the synthesis of dopamine in the surviving neurons of the substantia nigra. Parkinsonism results from insufficient dopamine in specific regions of the brain, attempts have now been made to replenish the dopamine deficiency. Dopamine itself does not cross the blood-brain barrier, but its immediate precursor (levodopa) is actively transported into the CNS and is converted to dopamine in the brain.

64.

A woman  was delivered to a hospital for trachea intubation. What of the following drugs  should  be applied  in this case?

Explanation

image

Dithylinum is a neuromuscular blocking drug (myorelaxants). It attaches to the N-cholinoreceptor depolarizing the junction and providing a constant stimulation of the receptor. The continued binding of the depolarizing agent renders the receptor incapable of transmitting further impulses. They are used to relax muscles during surgery.

65. An unconscious  young man with signs of  morphine poisoning  entered admission  office. His  respiration is shallow  and infrequent which  is caused  by inhibition of respiratory centre.  What  type of respiratory failure is it?

Explanation

Morphine is the major analgesic drug contained in crude opium. Opoids exert their major effects by interacting with opoid receptors in the CNS and in other anatomic structures, such as the GIT and the urinary bladder. Severe respiratory depression can occur and result in death from acute opoid poisoning. A serious effect of the drug is stoppage of respiratory exchange in patients with emphysema or Cor pulmonale. In this case, there is dysregulation of the respiratory center in the CNS.

66. A patient in postoperative period  was prescribed an anticholinesterase drug for stimulation of intestinal peristalsis  and tonus of urinary bladder. What drug is it?

Explanation

Proserin (neostigmine) is an indirect acting cholinergic agonist (anticholinesterase). It preserves endogenous acetylcholine which can stimulate a greater number of acetylcholine receptors at the muscle endplate. Thereby increasing intestinal peristalsis and tone of urinary bladder.

Dichlothiazide – thiazide diuretic; Reserpine – sympatholytic; Mannitol – Osmotic diuretic; Propanolol – β-adrenoblocker.

67. A patient suffering from initial hypertension has been taking an anti-hypertensive preparation  for  a  long  time. Suddenly  he stopped taking this preparation.   After    this   his   condition grew  worse,  this  led  to  development of hypertensive crisis. This by-effect  can be classified as:

Explanation

Abstinence syndrome is renewal or deterioration of the disease after cessation of the drug administration. It is the withdrawal symptoms that occur after abstinence/stoppage of a drug, especially after taking the drug for some relatively long time (e.g. a narcotic).

       Hypertensive crisis is a deterioration of the initial hypertension.

68. A    65   year    old    female    patient suffers from chronic renal insufficiency accompanied by evident  edemata caused by chronic  glomerulonephritis. What  diuretic  should  be administered for forced diuresis?

Explanation

IMG_9896

Bumetanide, furosemide, torsemide, ethacrynic acid are diuretics that have their major action on the ascending limb of the loop of henle (loop diuretics). These drugs are useful in emergency situation which calls for a rapid, intense dieresis (forced dieresis).

image

Loop or high-ceiling diuretics inhibit the co-transport of Na+/K+/2Cl- on the luminal membrane in the ascending limb of the loop of henle.

69. A   patient  suffering   from   chronic cardiac   insufficiency  was  recommended to undergo a prophylactic course  of treatment with a cardiological  drug  from the  group   of  cardiac   glycosides  that   is to be taken  enterally. What drug was recommended?

Explanation

 Cardiac glycoside is the most appropriate in this case. Cardiac glycosides are glycosidic drugs of plant origin having cardiac inotropic property, increase myocardial contractility and output.

Corglyconum is short acting for acute cardiac insufficiency and administered intravenously.

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Digitoxin is long-acting but basically administered orally and used mainly for chronic heart failure (also digoxin).

70. A  19  year  old  woman  suffers  from primary    syphilis.   Doctor   administered her complex therapy that includes benzylpenicillin sodium  salt. What  is the mechanism  of action of this drug?

Explanation

Penicillins inhibit the synthesis of bacterial cell walls and are considered bactericidal too.

image

They bind penicillin binding proteins (transpeptidases) and block transpeptidase cross-linking of peptidoglycan in cell wall. They also activate autolytic enzymes.

 Benzylpenicillin sodium is a short acting penicillin.

71.

A patient suffers from  diabetes melitus. After the regular insulin injection his condition grew worse:  there appeared anxiety, cold sweat, tremor of limbs, general weakness, dizziness. What preparation can eliminate these symptoms?

Explanation

The most common complication of insulin therapy is hypoglycemia. For treatment of hypoglycemia:

·        Intravenous injection of glucose solution 500 – 5%

·        Subcutaneous injection of glucagon 1.0ml

·        Subcutaneous injection of 1.0ml – 0.1% adrenaline hydrochloride (epinephrine)

72.

A  4 year  old  child  was  admitted to the orthopaedic department with shin fracture together with displacement. Bone fragments reposition requires preliminary analgesia. What preparation should be chosen?

Explanation

All options listed are all opoid analgesics; but Promedol remains the best answer because it has a spasmolytic effect (antispasmodic). Therefore, it is very effective for pains associated with spasms of smooth muscles of internal organs and blood vessels. In comparison with morphine hydrochloride, it has less oppressing activity on respiratory centers, less than excites the center of the vagus nerve and the vomiting center. When the pain is associated with spasms of smooth muscle (angina pectoris, liver, kidney, intestinal cramps) you can assign promedol with atropine, metacin, papaverine etc.

73. A   patient  suffering   from   infectious mononucleosis has been taking glucocorticosteroids for  two  weeks.  This  resulted in remission  but  the  patient got exacerbation of chronic tonsillitis. This complication is induced  by the  following effect of glucocorticosteroids:

Explanation

Glucocorticoids have immunosuppressive effects, anti-inflammatory effects, anti-shock, anti-allergic and anti-toxic effects. Immunosuppressive effects: glucocorticoids inhibit some of the mechanisms involved in cell-mediated immunologic functions, especially those dependent on lymphocytes. These agents are actively lymphotoxic and are important in the treatment of hematologic cancers. The drugs do not interfere with the development of normal acquired immunity but delay rejection reactions in patients with organ transplants. This immunosuppressive effect makes the patient susceptible to other infectious diseases (e.g. chronic tonsillitis).

74.

A patient ill with neurodermatitis has been  taking prednisolone for a long time. Examination revealed  high rate  of sugar in his blood.  This complication is caused by the drug influence  upon  the  following link of carbohydrate metabolism:

 

Explanation

Glucocorticoids (prednisolone) stimulate gluconeogenesis. As a result, blood sugar rises, muscle protein is catabolized and insulin secretion is stimulated. Corticosteroids cause increased gluconeogenesis, increased lipolysis, CNS effects - at times including euphoria, maintenance of cardiovascular function by potentiation of norepinephrine. Gluconeogenesis uses the reversible reactions from glycolysis and 4 distinct reactions that circumvent the ones from glycolysis that are irreversible. These reactions are catalyzed by pyruvate carboxylase, phosphoenolpyruvate carboxykinase, fructose-1, 6-bisphosphatase and glucose-6-phosphatase. Glucagon, epinephrine and glucocorticoids stimulate all these enzymes (excluding pyruvate carboxylase).

75. A healthy  man is in a region  with high risk of catching malaria. What drug should be administered for individual chemoprophylaxis of malaria?

Explanation

     Chingamin (chloroquine) prevents polymerization of the hemoglobin breakdown product (heme) into hemozoin.

image

Intracellular accumulation of heme is toxic to the parasite. It is a weak base and may buffer intracellular pH, thereby inhibiting cellular invasion by parasitic organisms. The drug is solely a blood schizonticide (erythrocytic) and will not eradicate secondary tissue schizonts. It is the drug of choice for acute attacks, prophylaxis and treatment of malaria, has been used in amebic liver disease in combination with metronidazole and in autoimmune disorders including rheumatoid arthritis, systemic lupus erythematous (interstitial disease).

76.

A  patient who  suffers  from  insomnia caused by emotional disorder was prescribed a hypnotic drug with tranquillizing effect. What hypnotic  was prescribed?

 

Explanation

All of the benzodiazepines used to treat anxiety (tranquilizers) have some sedative properties and some can produce hypnosis (artificially produced sleep) at higher doses. Their effects have been shown to be mediated by the α1-GABAA receptors. Benzodiazepines are the most widely used anxiolytic drugs e.g. Diazepam, lorazepam, nitrazepam, clonazepam etc. They are also used to treat neurosis.

77. A woman works as railway traffic controller. She suffers from seasonal vasomotor rhinitis  and  gets  treatment in the outpatient setting. She was prescribed an antihistamine that  has no effect  upon central  nervous  system. What drug is it?

Explanation

     Loratadine is an antihistamine (antiallergic drug) which refers to the classic H1-receptor blocker. These compounds do not influence the formation or release of histamine. Rather, they block the receptor-mediated response of a target tissue. They are much more effective in preventing symptoms than reversing them once they have occurred. These agents, desloratadine, fexofenadine, and loratadine show the least sedation i.e. least effect on CNS (they don’t induce sleep).

78. An  unconscious   patient  was  delivered   to  the   admission   ward.   Objectively: the  patient’s skin is cold, pupils are myotic,  he  has  laboured Cheyne-Stokes respiration, arterial pressure is low,  urinary  bladder is full. What  substance  has caused intoxication?

Explanation

Acute poisoning with narcotic analgesics (e.g. morphine) is characterized by sleep or unconsciousness, normal or increased reflexes, normal muscle tone, miosis, bradycardia, cheyne-stokes breath, the retention of urine, a spasm of intestine and bowel. This condition can be treated with:

·        Stomach lavage with 0.5% solution of potassium permanganate.

·        Intravenous injection of Naloxone (naloxone is an antagonist of narcotic analgesic).

·        Atropine; for decrease in the vagal action of morphine.

79. In  order  to  accelerate healing  of  a radiation ulcer  a vitamin  drug was administered. What drug is it?

Explanation

     Several studies, such as the one published in the June 2008 edition of the “Journal of vascular nursing”, have shown reduced levels of vitamin A in patients suffering from leg ulcers, indicating a connection between the two, probably because vitamin A helps to form and maintain healthy skin, mucous membrane and teeth. Vitamin A and the amino acid glutamine help to regenerate healthy epithelial cells.

80. A  patient who  has  been  treated  in a  neural   clinic  and  has  been   taking   a sedative  for  a long  time  got  the  following complication: cough, rhinitis, epiphora. What drug caused these disturbances?

Explanation

     Doses of bromides have to be determined individually. The bromides are excreted from the organism rather slowly (50-60days), so they may be accumulated and cause the signs of chronic poisoning (bromism). The irritative action of bromides leads to inflammation of the mucous membranes which is accompanied by cough, rhinitis, conjunctivitis and diarrhea.

81. An alcoholic  has alcoholic  psychosis with evident psychomotor agitation. What neuroleptic drug  should  be administered  for emergency  care?

Explanation

·        Aminazine – neuroleptic (it is better than reserpine for emergency care. It has also proved to be useful in control of intracted hiccup).

·        Diazepam – tranquilizer

·        Sodium bromide – sedative

·        Reserpine – neuroleptic

·        Halothane – general anesthesia

82.

Study of conversion  of a food colouring agent  revealed  that  neutralization of this  xenobiotic   takes  place  only  in  one phase  - microsomal   oxidation.   Name  a component of this phase:

Explanation

     The P450 system is impotant for the metabolism of many endogenous compounds (such as steroids, lipids etc) and for the biotransformation of exogenous substances (xenobiotics). Cytochrome P450, designated as CYP, is a superfamily of heme-containing isozymes that are located in most cells but are primarily found in the liver and GIT. Phase I reactions utilizing the P450 system (also called microsomal mixed function oxidases). The oxidation proceeds by the xenobiotic binding to the oxidized form of cytochrome P450 and then O2 is introduced through a reductive step, coupled to NADPH: cytochrome P450 oxidoreductase.

83. A  patient with  myocardial  infarction was admitted to the cardiological department. For  pain  relief  it  was  decided   to   potentiate  fentanyl   action   with  a  neuroleptic.  Which  of  the  following  neuroleptics is the  most  suitable  for neuroleptanalgesia?

Explanation

     Droperidol is often combined with a potent narcotic analgesic such as fentanyl to produce neuroleptanalgesia. It is used for neuroleptanalgesia because of its quick effect (action), short duration of action, myorelaxant and antihypertensive effects. Droperidol has quick and short effects, produces hypotension and myorelaxantia.

         Fentanyl + Droperidol = Talomonal (neuroleptanalgesia)

84. A doctor  prescribed a cephalosporin antibiotic to the patient after appendectomy for  infection   prevention.  Antimicrobial activity of this group of antibiotics  is based upon   the   disturbance  of  the   following process:

Explanation

     The cephalosporins are β-lactam antibiotics that are closely related both structurally and functionally to the penicillins. Cephalosporins like the penicillns, inhibit bacterial cell wall synthesis and are considered bactericidal against susceptible organisms.

image

         Penicillins inhibit the synthesis of bacterial cell walls and are considered bactericidal too. They bind penicillin binding proteins (transpeptidases) and block transpeptidase cross-linking of peptidoglycan in cell wall. They also activate autolytic enzymes.

85.

A  female  patient was administered loratadine for allergic cheilitis treatment. What is the mechanism  of the drug’s action?

 

Explanation

     Loratadine is an antihistamine (antiallergic drug) which refers to the classic H1-receptor blocker. These compounds do not influence the formation or release of histamine. Rather, they block the receptor-mediated response of a target tissue. They are much more effective in preventing symptoms than reversing them once they have occurred. These agents, desloratadine, fexofenadine, and loratadine show the least sedation i.e. least effect on CNS (they don’t induce sleep).

86. During     anesthetization   a    patient presented with symptoms of tonus increase  of  parasympathetic nervous system such as hypersalivation and laryngospasm. What drug could have prevented these undesirable effects?

Explanation

image Acetylcholine is a neurotransmitter. The only neurotransmitter used by parasympathetic nervous system. It increases salivary secretion and stimulates intestinal secretions and motility. It increases bronchial secretions, increases tone of detrusor urinae muscle, causing expulsion of urine, stimulates ciliary muscle contraction (accommodation). It increases exocrine gland secretions (e.g. lacrimal, salivary, gastric acid); gut peristalsis, bladder contraction, bronchoconstriction, papillary sphincter muscle contraction (miosis). image Poisoning by cholinomimetics causes diarrhea, urination, miosis, bronchospasm, bradycardia, excitation of skeletal muscle and central nervous system, lacrimation, sweating and salivation. Atropine sulfate (M-cholinoblocker) blocks the acetylcholine effect.
87.

A female  patient consulted  a doctor about a sense of epigastric discomfort, nausea  and anorexia. A duodenal content analysis revealed lamblia.   What   drug should be prescribed?

Explanation

Metronidazole forms toxic free radical metabolites in the bacterial cell that damage DNA. It is bactericidal, and an antiprotozoal. It is used to treat Giardia lamblia, Entamoeba histolytica, Trichomonas, Gardnerella vaginalis, Anaerobes (bacteroides, Clostridium difficile). It can be used with a proton pump inhibitor and clarithromycin for “triple therapy” against Helicobacter pylori.

88.

A  patient takes  digoxin  for  cardiac insufficiency.  What  diuretic  may increase digoxin toxicity due to the intensified excretion of K + ions?

Explanation

IMG_9896     

Hydrochlorothiazide is a thiazide diuretic. Thiazide diuretics induce hypokalemia and hyperuricemia in 70% of patients and hyperglycemia in 10% of patients.

image

Serum potassium levels should be monitored closely in patients who are predisposed to cardiac arrhythmias (particularly individuals with left ventricular hypertrophy, ischemic heart disease or chronic heart failure) and those who are concurrently being treated with both thiazide diuretics and digoxin. In general, decreased serum levels of potassium predispose a patient to digoxin toxicity.

89.

A   patient  with   coronary    disease and  arrhythmia has been  administered a drug that blocks potassium channels and prolongs  the  action  potential. What  drug is it?

Explanation

     Class III antiarrhythmic drugs block potassium (K+) channels and thus diminish the outward potassium current during repolarization of cardiac cells. These agents prolong the duration of the action potential without altering phase O of depolarization or the resting membrane potential. Class III drugs include amiodarone, dronedarone, sotalol, dofetilide.

Corglyconum – short acting cardiotonic; it’s a cardiac glycoside (for acute heart failure).

Nitroglycerine – organic nitrate

Dobutamine – β1 agonist; it’s a nonglycoside cardiotonic

Lisinopril – angiotensin converting enzyme (ACE) inhibitor

90.

If a man  has  an  attack  of bronchiospasm it is necessary to reduce  the effect of vagus  on  smooth  muscles  of bronchi. What  membrane cytoreceptors should  be blocked for this purpose?

Explanation

Muscarinic receptors belong to the class of G protein-coupled receptors. These receptors, in addition to binding Acetylcholine, it also recognizes muscarine – an alkaloid that is present in certain poisonous mushrooms. Muscarinic effects include miosis, spasm of accommodation, increasing of lacrimal, salivary, gastrointestinal, bronchial and sweat glands secretion, increase of smooth muscle tonus of internal organs, bradycardia, decreased arterial pressure.

M-cholinoreceptors increase muscle tonus of internal organs. Therefore blocking this receptor will relieve the bronchospasm.

91.

During surgical manipulations a patient has been given novocaine  injection for anesthesia. 10 minutes  later  the  patient developed paleness,  dyspnea,  hypotension. What type of allergic reaction is it?

Explanation

Considering the time (10mins) – immediate

Type I Hypersensitivity reaction (HSR); anaphylactic and atopic: free antigen cross-links IgE on presensitized (i.e. exposed to the antigen before) mast cells and basophils, triggering immediate release of vasoactive amines that act at postcapillary venules (i.e. histamine). Reaction develops rapidly after antigen exposure because of preformed antibody from first exposure. IgE is the main immunoglobulin involved in type I HSR. Type I: uses IgE and IgG4

92. A female  patient consulted  a doctor about   pain   and   limited   movements  in the   knee   joints.  Which  of  the  following nonsteroid anti-inflammatory drugs should  be administered taking into consideration that  the  patient has a history  of chronic gastroduodenitis?

Explanation

The nonsteroidal anti-inflammatory drugs (NSAIDs) are a group of chemically dissimilar agents that differ in their antipyretic, analgesic and anti-inflammatory activities. They act primarily by inhibiting the cyclooxygenase (COX 1 and 2) enzymes that catalyze the first step in prostanoid biosynthesis. This leads to a decrease prostaglandin synthesis with both beneficial and unwanted effects. Aspirin is one of the most important NSAID. Its most common side effect is its gastrointestinal (GI) effect. Normally, prostacyclin (PGI2) inhibits gastric acid secretion, whereas PGE2 and PGF stimulate synthesis of protective mucus in both the stomach and small intestine.

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In the presence of aspirin, these prostanoids are not formed, resulting in increased gastric secretion and diminished mucus protection. This may cause epigastric distress, ulceration, hemorrhage and iron-deficiency anemia.

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Celecoxib is a selective cyclooxygenase 2 (COX-2) inhibitor. Approved for treatment of rheumatoid arthritis, osteoarthritis, acute to moderate pain, also approved for patients with peptic ulcers or gastroduodenitis.

93. A patient with acute myocardial infarction has been administered heparin as   a   part   of   complex   therapy.  Some time   after   heparin  injection   the   patient  developed hematuria. What  heparin antagonist should  be injected  in order  to manage the complication?

Explanation

Heparin is a natural anticoagulant produced in mast cells and basophils. It is an injectable, rapidly acting anticoagulant that is often used acutely to interfere with the formation of thrombi. Heparin is used in the prevention of venous thrombosis and the treatment of a variety of thrombotic diseases such as pulmonary embolism and acute myocardial infarction. Heparin binds to antithrombin III, with the subsequent rapid inactivation of coagulation factors. Antithrombin III inhibits serine proteases, including several of the clotting factors, most importantly, thrombin (factor IIa) and Factor Xa (a-active).

Protamine sulphate antagonizes the anticoagulant effects of heparin. The positively charged protamine interacts with the negatively charged heparin forming a stable complex without anticoagulant activity.

94.

A  liquidator of  a  breakdown  at  a nuclear  power  plant  who  was irradiated complained about  vomiting that occurs all of a sudden.  What  medication should  be prescribed?

Explanation

     Metoclopramide is an antiemetic drug; an antidopamine. It blocks D2-dopamine receptors of emetic center in the CNS. It has a central antiemetic effect in vomiting of any genesis. Uses – vomiting induced by irritation of gastrointestinal mucous membrane, post-operative period, pregnancy toxicosis, radiation sickness etc.

95. A  17-year-old  girl  took  a  high  dose of   phenobarbital   to   commit    a   suicide. An ambulance doctor  cleansed her stomach and gave her an intravenous injection of bemegride and sodium hydrocarbonate solution.  What  was sodium hydrocarbonate injected for?

Explanation

     Sodium hydrocarbonate/sodium bicarbonate is a systemic alkalinizing agent which when given intravenously will increase plasma bicarbonate, buffer excess hydrogen ion concentration, raise blood pH and reverse the clinical manifestations of acidosis. Sodium bicarbonate is used to increase urinary pH in order to increase the solubility of certain weak acids (e.g cystine, sulphonamides, uric acid) and in the treatment of certain intoxications (e.g. methanol, Phenobarbital, salicylates) to decrease renal reabsorption of the drug or to correct acidosis.

96.

Examination  of  a  70-year-old   patient  revealed  insulin-dependent diabetes. What drug should be administered?

Explanation

Sulfonylurea are insulin secretagogues because they promote insulin release from the β-cells of the pancreas. The primary drugs used today are the 2nd generation drugs – glibenclamide, glipizide, glimepiride etc. These agents are useful in the treatment of patients who have type 2 diabetes mellitus and cannot be managed by diet alone. Glibenclamide is much more potent and used commonly. 

NB: A 70-year-old patient has greater propensity for type 2 diabetes mellitus.

97. This drug  has  a destructive effect  on erythrocytic forms  of malarial  plasmodia and  dysenteric amoebae.  It  is  used  for treatment and prevention of such diseases as malaria,  amebiasis  and  interstitial disease. What drug is it?

Explanation

     Chingamin (chloroquine) prevents polymerization of the hemoglobin breakdown product (heme) into hemozoin.

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Intracellular accumulation of heme is toxic to the parasite. It is a weak base and may buffer intracellular pH, thereby inhibiting cellular invasion by parasitic organisms. The drug is solely a blood schizonticide (erythrocytic) and will not eradicate secondary tissue schizonts. It is the drug of choice for acute attacks, prophylaxis and treatment of malaria, has been used in amebic liver disease in combination with metronidazole and in autoimmune disorders including rheumatoid arthritis, systemic lupus erythematous (interstitial disease).

98.

Which of the listed diuretic agents WILL NOT have diuretic  effect on a patient with Addison’s disease?

Explanation

    Addison’s disease is chronic adrenal insufficiency (hypoaldosteronism). Spironolactone is an aldosterone antagonist. In addison’s disease, there is no aldosterone or it is very low; therefore, spironolactone will not have any effect on such patient.

99. A patient with cardiogenic  shock, hypotension, asphyxia  and  edemata was given an injection  of non-glycosidic cardiotonic. What drug was injected?

Explanation

     Non-glycoside cardiotonics includes β1-adrenergic agonists, phosphodiesterase inhibitors, these drugs prolong synthesis of ATP and have positive inotropic property and increase cardiac output.

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Dobutamine – β1-adrenergic agonists

Caffeine sodium benzoate; Cordiamin; Aethimizolum and Bemegride – Analeptics.

100. A  patient with  essential  hypertension  has  a high  rate  of blood  renin.  Which of antihypertensive drugs should be preferred?

Explanation

Lisinopril is an angiotensin converting enzyme inhibitor (ACE Inhibitor). This drug block the ACE that cleaves angiotensin I to form the potent vasoconstrictor angiotensin II. Rennin converts angiotensinogen to angiotensin I.

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Propranolol is a β-blocker; Prazosin – α1-adrenoblocker; Nifedipine – Ca2+-channel blocker; Dichlothiazide – thiazide diuretic.

For a high rate of renin, the antihypertensive drugs that are effective are: renin inhibitor (Aliskiren); angiotensin II receptor blocker and angiotensin converting enzyme (ACE) inhibitors because they block the renin –angiotensin system.

101.

A 65-year-old  female patient has chronic constipations due to the colon hypotonia. What  drug  should  be  chosen in this case?

Explanation

Constipations requires the use of laxatives that will stimulate the movement of food through gastrointestinal tract (GIT), produce soft formed stool and accelerate defecation. Bisacodyl is typically prescribed for relief of constipation and for the management of neurogenic bowel dysfunction as well as part of bowel preparation before medical examinations, such as for a colonoscopy. Bisacodyl works directly on the colon to produce bowel movement. It works by stimulating enteric nerves to cause colonic mass movements (contractions); removing the colon hypotonia.

102. A patient with bacterial periodontitis has  been  administered iontophoresis with the  use of iodine  solution.  Specify the mechanism  of  therapeutic action  of  this agent:

Explanation

103.

 A patient who had been continuously taking  drugs  blocking  the  production of angiotensin II developed bradycardia and arrhythmia. A likely cause of these disorders is:

Explanation

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Angiotensin converting enzyme (ACE) inhibitors block the production of angiotensin II from angiotensin I e.g. Lisinopril, Enalapril

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The side effect of this group of drug is dry cough, rash, fever, hypotension, hyperkalemia. Hyperkalemia can cause bradycardia and arrhythmia.

104.

A patient with arthritis and varicose veins has been taking a non-steroidal anti-inflammatory drug for a long time, which caused  thrombosis of  skin  veins.  Which of the following drugs might have caused this complication?

Explanation

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Celecoxib is a selective cyclooxygenase 2 (COX-2) inhibitor. Approved for treatment of rheumatoid arthritis, osteoarthritis, acute to moderate pain, also approved for patients with peptic ulcers or gastroduodenitis. Selective COX-2 inhibitors lack disaggregative properties (i.e. they can’t prevent platelet aggregation), unlike non-selective inhibitors of COX-1 and COX-2.

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Therefore, there is probability of development of thrombosis when used alone. All other options are non-selective inhibitors of COX-1 and COX-2; which means they have disaggregating properties (especially aspirin).

105.

A  patient has  recurrent attacks   of epileptic seizures and stays unconscious between them.  In order  to stop  convulsions   the   drugs   of  the   following   group should be used in the first place:

Explanation

Tranquilizers (anxiolytics) are drugs which reduce state of internal tension, morbid phobia and anxiety, they are used to treat neurosis. Because many tranquilizers also cause some sedation, they can function as both anxiolytic and hypnotic (sleep-inducing) agents, some also have anticonvulsant activity (epileptic seizures). Analeptics (CNS, respiratory stimulants); Neuroleptics (antischizophrenic, antipsychotic); Sedatives (decrease excitement without inducing sleep).

106.

A  26-year-old  woman  at  40 weeks pregnant has been  delivered  to the maternity ward.  Objectively:  the  uterine cervix is opened, but the contractions are absent.  The  doctor  has administered her a hormonal drug  to  stimulate the  labor. Name this drug:

 

Explanation

Oxytocin is a hormonal drug inducing rhythmic uterine contractions by acting on myometrium cell membranes, increasing their excitability. Oxytocin remains the strongest stimulator of uterine contractions. Estrone is a female sex hormone, but small amounts are also produced in adrenal cortex in both sexes. It’s effects on labour is probably to stimulate cervical ripening through prostaglandin synthesis and not on uterine contraction. The other options are also related to the adrenal gland but no direct effect on uterine contraction.

107.

A hypertensive patient had been keeping to a salt-free diet and taking  antihypertensive drugs  together with hydrochlorothiazide for a long time. This resulted in  electrolyte imbalance. What disorder  of the internal environment occurred in the patient?

Explanation

Hydrochlorothiazide is a thiazide diuretic which acts mainly in the distal convoluted tubule to decrease the reabsorption of Na+, apparently by inhibition of a Na+/Cl- co-transporter on the luminal surface of the tubules.

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Therefore, thiazide diuretics cause diuresis with increase Na+ and Cl-  excretion; Hypochloremic alkalosis results from either low chloride intake or excessive chloride excretion (thiazide diuretics). Low chloride intake (salt-free diet) is very uncommon, excessive chloride excretion often occurs in hospitalized children, usually as a result of diuretic therapy (e.g. thiazide diuretic) or nasogastric tube suctioning.

108.

A 12-year-old child has a viral infection  complicated  by  obstructive  bronchitis. Bronchospasm can  be  eliminated by inhalations of a drug  from  the  following pharmacological group:

Explanation

β2-receptors on the bronchial smooth muscle cause bronchodilation which can relieve the bronchospasm (sympathetic effect).

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β2 adrenergic blockers will increase the bronchospasm and make the patients condition worst.  N-cholinomimetics will have similar effects as β2 adrenergic blockers. M-anticholinergics (e.g. scopolamine) have dilatory effects but β2 agonists (e.g. salbutamol, fenoterol, salmoterol) remains the best drugs for relieving bronchoconstriction (bronchospasm) without significant cardiac stimulation unlike M-cholinoblocker which might likely increase cardiac activity by inhibiting vagus effect on heart.

109.

A 50-year-old  patient with food poisoning is on a drip of 10% glucose solution. It not only provides the body with necessary  energy,  but  also  performs the function of detoxification by the production of a metabolite that participates in the following conjugation reaction:

Explanation

Substances that cause food poisoning are xenobiotics, since they are foreign to the body. The body removes xenobiotics by xenobiotic metabolism, which takes place in the liver. Hepatic enzymes (e.g. cytochrome P450) first activate them- phase I (by oxidation, reduction, hydrolysis and/or hydration of the xenobiotic) and then conjugating the active secondary metabolite (phase II) with glucuronic acid, sulphuric acid or glutathione, followed by excretion in bile or urine. Glucuronidation is the most common and the most important conjugation reaction (glucuronidation – conjugation with glucuronic acid).

110.

A patient has been  administered an anti-inflammatory drug that blocks the action of cyclooxygenase.   Specify this anti-inflammatory agent:

Explanation

The nonsteroidal anti-inflammatory drugs (NSAIDs) are a group of chemically dissimilar agents that differ in their antipyretic, analgesic and anti-inflammatory activities. They act primarily by inhibiting the cyclooxygenase (COX 1 and 2) enzymes that catalyze the first step in prostanoid biosynthesis.

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This leads to decrease prostaglandin synthesis with both beneficial and unwanted effects. Aspirin is one of the most important NSAID. Its most common side effect is its gastrointestinal (GI) effect. Normally, prostacyclin (PGI2) inhibits gastric acid secretion, whereas PGE2 and PGF stimulate synthesis of protective mucus in both the stomach and small intestine. In the presence of aspirin, these prostanoids are not formed, resulting in increased gastric secretion and diminished mucus protection. This may cause epigastric distress, ulceration, hemorrhage and iron-deficiency anemia. Analgin is also an NSAID, but aspirin (acetylsalicylic acid) is far more preferable and more common pharmacologically.

111.

A  46-year-old   female  is  scheduled for  a  maxillofacial   surgery.  It  is  known that  the  patient is prone  to  high  blood coagulation. What  natural anticoagulant can be used to prevent blood clotting?

Explanation

Heparin is a natural anticoagulant produced in mast cells and basophils. It is an injectable, rapidly acting anticoagulant that is often used acutely to interfere with the formation of thrombi. Heparin is used in the prevention of venous thrombosis and the treatment of a variety of thrombotic diseases such as pulmonary embolism and acute myocardial infarction. Heparin binds to antithrombin III, with the subsequent rapid inactivation of coagulation factors.

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Antithrombin III inhibits serine proteases, including several of the clotting factors, most importantly, thrombin (factor IIa) and Factor Xa (a-active).

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Protamine sulphate antagonizes the anticoagulant effects of heparin. The positively charged protamine interacts with the negatively charged heparin forming a stable complex without anticoagulant activity.

112.

Infectious diseases  are  treated  with antibiotics  (streptomycin, erythromycin, chloramphenicol). They inhibit the following stage of protein synthesis:

Explanation

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Streptomycin (aminoglycoside) is a 30S ribosomal subunit inhibitor.

Erythromycin (macrolide); Chloramphenicol – 50S subunit inhibitor

Protein synthesis inhibitors specifically target smaller bacterial ribosome (70S –made of 30S and 50S subunits), leaving human ribosome (80S) unaffected. All these drugs block the translation of information on mRNA to protein.

113. A  66-year-old   patient  with  Parkinson’s disease  shows an improvement in locomotor  activity   after   prolonged  use of  a  certain  drug  which  is converted to dopamine by the  decarboxylation. What drug has the patient taken?

Explanation

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Levodopa is a metabolic precursor of dopamine. Because parkinsonism results from insufficient dopamine in specific regions of the brain, attempts have been made to replenish the dopamine deficiency. Dopamine itself does not cross the blood-brain barrier, but its immediate precursor – levodopa, is actively transported into the CNS and is converted to dopamine in the brain. Large doses of levodopa are required, because much of the drug is decarboxylated to dopamine in the periphery, resulting in side effects that include nausea, vomiting, cardiac arrhythmias and hypotension.

Celecoxib: NSAIDs (selective COX-2 inhibitor); indications – rheumatoid arthritis

Droperidol: typical neuroleptic; indications – psychoses, schizophrenia

Chlorpromazine (aminazine): same group and indication as droperidol

Naloxone : opoid antagonist; indications – acute poisoning with narcotic analgesics.

114. A patient with urolithiasis has unbearable  spasmodic   pain.  To  prevent pain shock, he has been given an injection of atropine along with a narcotic analgesic having  antispasmodic  effect.  What  drug was it?

Explanation

All options listed are all opoid analgesics; but Promedol remains the best answer because it has a spasmolytic effect (antispasmodic). Therefore, it is very effective for pains associated with spasms of smooth muscles of internal organs and blood vessels. In comparison with morphine hydrochloride, it has less oppressing activity on respiratory centers, less than excites the center of the vagus nerve and the vomiting center. When the pain is associated with spasms of smooth muscle (angina pectoris, liver, kidney, intestinal cramps) you can assign promedol with atropine, metacin, papaverine etc.

115.

Despite the  administration of  cardiotonics   and  a  thiazide   diuretic   a  patient  with  chronic  heart  failure  has  persistent  edemata, there  is a risk  of ascites. What  medication should  be administered in order  to enhance the diuretic  effect of the drugs used?

Explanation

K+ sparing diuretics:

  - aldosterone antagonist: spironolactone, eplerenone

  - inhibit Na+ reabsorption: triamterene

The answer is Spironolactone because after the administration of cardiotonics and a thiazide diuretic, if the edema still persists, it is probably due to an increased action of aldosterone on the principal cells in collecting tubule of the kidney. In this case, an aldosterone antagonist will enhance the diuretic effect to prevent the occurrence of ascites. Blocking aldosterone effect prevent further reabsorption of Na+ and H2O which will definitely enhance the diuretic effect. Aldosterone acts on mineralocorticoid receptor → mRNA → protein synthesis (synthesis of Na+ channels). Spironolactone prevents/blocks the synthesis of Na+ channels.

116. In order to stimulate breathing in a child born with asphyxia, the doctor gave him a drug  injection  into  the  umbilical  vein. What drug might have been injected?

Explanation

Analeptics (aethimizolum): drugs which act upon the CNS general functions, but stimulate mainly medulla oblongata (respiratory, cardiovascular centers). Aethimizolum acts on the medulla with a direct action.

Aethimizolum also activates the adrenocorticotropic pituitary function which increase cortisol level → ↑production of surfactant. All other options are analeptics but they are only used in the absence of aethimizolum in case of children born with asphyxia.

117.

To prevent attacks  of acute  pancreatitis a doctor  prescribed the patient trasylol (contrycal, gordox),  which is an inhibitor of:

Explanation

Acute pancreatitis is an Inflammatory reaction characterized by autodigestion of pancreas by pancreatic enzymes (proteolytic enzymes). Contrycal (Aprotinin, Gordox)- protease inhibitor;  Aprotinin (contrycal, gordox) – antitrypsin; antiprotease. Therefore,it can inhibit the proteolytic enzymes digesting the pancreas.
118.

It   is  known   that individuals with genetically  caused  deficiency  of glucose-6-phosphate dehydrogenase may develop RBC hemolysis in response to the administration of some antimalarial drugs. Manifestation  of adverse  reactions to drugs  is called:

 

Explanation

Idiosyncrasy and allergic reaction is as a result of organism’s increased sensitivity to the drugs. It’s a complication of pharmacological therapy (adverse reactions). Tolerance and Tachyphylaxis are effects of repeated doses.

* Idiosyncrasy is genetically conditioned perverse organism’s response to drugs (e.g. inefficiency, lack of enzymes participating in drug metabolism). Genetic deficiency of glucose 6-phosphate dehydrogenase (hereditary enzymopathy). This enzyme is needed for proper functioning of glutathione (an antioxidant) to prevent the oxidative effect of antimalarial drugs on the RBCs.

* Allergic reactions results from antibody production against some drugs.

* Tachyphylaxis is quick weakening of the effect, sometimes may occur after first drug introduction (usually connected with substrate exhaustion).

* Tolerance (habituation): is increasing of the effects in repeated doses resulting from decreasing of absorption, speed-up of the biotransformation or excretion, or decreasing of the receptors sensitivity.

119.

Curariform substances  introduced into  a  human   body  cause  the  relaxation of all skeletal  muscles.  What  changes in the  neuromuscular synapse  cause  this phenomenon?

Explanation

The first drug that was found to be capable of blocking the skeletal neuromuscular junction (NMJ) was curare, which native South American hunters of the Amazon region used to paralyze prey. The drug tubocurarine was ultimately purified and introduced into clinical practice in the early 1940s. Muscarinic and Nicotinic receptors are the two cholinergic receptors (cholinoreceptors). Nicotinic receptors are located in the CNS, adrenal medulla, autonomic ganglia and the NMJ. Those at the NMJ are the ones that are blocked by Curariform substances.

120.

A comatose  patient was taken  to the hospital. He has a history of diabetes mellitus.Objectively:   Kussmaul  breathing, low blood  pressure, acetone odor  of breath.  After   the  emergency   treatment the  patient’s   condition  improved.   What drug  had  been  administered to the  patient?

Explanation

The described symptoms are for type I diabetes mellitus (especially acetone odor of breath as a result of excess ketone bodies). Type I diabetes mellitus is due to decrease or absent insulin. Insulin facilitates the transport of glucose and amino acids into target organs: In liver – insulin increases the storage of glucose as glycogen. It decreases protein catabolism; In muscles – it stimulates glycogen synthesis and protein synthesis; In Adipose tissue – it facilitates triglyceride storage by activating plasma lipoprotein lipase which increase glucose transport into the cell and by reducing intracellular lipolysis.

Glibenclamide is typically used for type 2 diabetes mellitus.

Adrenaline will further exacerbate the hyperglycemic condition because it stimulates glycogen phosphorylase. Isadrinum is a non-selective β12 adrenergic agonists (β-adrenomimetics); it’ll have the same effect as adrenaline. Furosemide is a loop diuretic and will not correct the comatose state of the patient; It has no effect on glucose metabolism or ketone bodies.

121.

A   patient  with   biliary   dyskinesia and  constipations has  been  prescribed a cholagogue having  also a laxative  effect. What drug has been administered?

Explanation

Allochol and cholenzyme are agents of biliary acids and bile (cholesecretics – induce bile secretion). Cholosas is a plant agent (cholesecretics – induce bile secretion). Nicodinum is a synthetic agent (cholesecretics – induce bile secretion). They all stimulate bile formation. Magnesium sulfate is a drug causing gall bladder contraction and relaxation of sphincter of oddi; it promotes bile excretion. It is also a salt laxative acting on all intestine’s secretions. It is a non-absorbable salt that hold water in the intestine by osmosis and distend the bowel, increasing intestinal activity and producing defecation.

122. A 50-year-old  patient has been  administered laevomycetin for the treatment of typhoid fever, but on the next day the patient’s condition worsened, the temperature rose  to 39, 60C . The  deterioration of the patient’s condition can be explained  by:

Explanation

Endotoxins: outer cell membrane of most gram negative bacteria. It is not secreted from the cell. It is the structural part of bacteria (lipopolysaccharide) released when the bacteria is lysed. It was originally theorized that endotoxin is released once the bacteria dies. It is now a known fact that bacteria release small amounts of endotoxin as a part of their normal metabolism although the majority is still retained inside the cell. So when the laevomycetin is used, it kills the bacteria but the deterioration of the patient’s condition is as a result of the endotoxin released when the bacteria died. Effects of endotoxin: fever, hypotension, edema, DIC.

123.

During  a surgery with the use of hygronium the patient had an abrupt fall in blood  pressure. Blood  pressure can be normalized by the  representatives of the following drug group:

Explanation

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Hygronium is a ganglioblocker. They can cause dilatation of arteries and veins that leads to an DECREASE of arterial pressure. To normalize Blood pressure (BP), we can use alpha-adrenergic agonists which will cause constriction of smooth muscles in peripheral arterioles.

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INCREASE in peripheral resistance will lead to INCREASE BP. Alpha-blockers and Ganglio-blockers will further lead to hypotension. M&N-cholinergic agonist does not have significant effect on BP.

124.

A  patient with a dislocated shoulder had  been  admitted  to  a  hospital.   With the  purpose of  skeletal muscle  relaxation he was given an injection  of relaxant dithylinum acting  normally  5-7 minutes. However, the  effect  of dithylinum  in this patient lasted  up to 8 hours.  What  is the most  likely cause of the prolonged effect of dithylinum in this patient?

Explanation

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Dithyllium is a depolarizing myorelaxant (neuromuscular blocking drug). They are used as adjuvant drugs in anaesthesia during surgery to relax skeletal muscles. An absence or deficiency of acetylcholinesterase/pseudocholinesterase enzyme leads to a silent condition that manifests itself only when people that have the deficiency receive the muscle relaxants.

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This enzyme plays an important role in  the metabolism of ester-based local anesthesics, a deficiency of blood cholinesterase can prolong the effect of dithylinium from just 5-7minutes to 8hours.

125.

A   40-year-old    female   patient  diagnosed  with acute  pancreatitis has been delivered to the admission  department of a regional  hospital.  What  drug should  be administered the patient in the first place?

Explanation

Acute pancreatitis is an Inflammatory reaction characterized by autodigestion of pancreas by pancreatic enzymes (proteolytic enzymes). Contrycal (Aprotinin, Gordox)- protease inhibitor. Therefore,it can inhibit the proteolytic enzymes digesting the pancreas. Platyphyllin hydrotartras, Metacin, Pirenzepine, Atropine Sulfate – M-cholinoblockers. Contrycal also has antifibrinolytic (antiplasmin) and hemostatic effect.
126.

A   female    patient  with   bronchial asthma  had taken  prednisolone tablets  (1 tablet  3 times a day) for 2 months.  Due to a significant improvement of her condition the patient suddenly  stopped taking it. What  complication is likely to develop  in this case?

 

Explanation

One of the major setbacks related to continuous, long term steroid (cortisol, prednisolone). Treatments are symptoms due to changes in the balance of normal hormone secretion. This typically results from taking doses greater than our body’s natural production. Once we begin to decrease or discontinue the dose, however, withdrawal symptoms may occur. Thus, steroids are typically given for the shortest time possible. Short-term use does not induce steroid withdrawal syndrome. In general, the longer you are on this steroid, the longer it is going to take your body to readjust to functioning without it. If you are on it for longer than 2 weeks, it can affect your adrenal glands ability to produce cortisol.

127. A girl receives antibiotics of the penicillin group for acute bronchitis.  On the third day of treatment she developed allergic dermatitis. Which drug should be administered?

Explanation

Loratidine : Antihistamine (antiallergic) block H1-histamine receptors as well as adrenergic, cholinergic & serotonin-binding recpetors. They do not influence the formation or release of histamine, but rather they competitively block the receptor-mediated response of target tissue.                                                                                           Cromolyn Sodium: Membrane stabilizers, anti-allergic but it is the best for prophylaxis (prevention) & not for treatment of allergic conditions. Beclomethasone: Synthetic glucocorticoids and anti-inflammatory.  Ephedrine hydrochloride: Adrenomimetic.                                   Levamisole: Synthetic immunostimulator.
128. Some infectious diseases caused by bacteria are treated with sulfanilamides which  block the synthesis of bacteria growth factor. What is the mechanism of their action?

Explanation

IMG_9914

Sulfonamides inhibit folate synthesis. They also act as antimetabolites of para-amino benzoic acid PABA by inhibiting dihydropteroate synthase.

129.

A   42-year-old    male   patient  with gout has an increased blood uric acid concentration. In order to reduce the level of uric acid the  doctor  administered him allopurinol. Allopurinol is the  competitive inhibitor of the following enzyme:

Explanation

imageimage Allopurinol is a purine analog. It reduces the production of uric acid by competitively inhibiting the last two steps in uric acid biosynthesis that are catalyzed by xanthine oxidase. NOTE: Uric acid is less water soluble than its precursors. When xanthine oxidase is inhibited, the circulating purine derivatives (xanthine & hypoxanthine) are more soluble and therefore are less likely to precipitate.
130.

A 60-year-old  patient with a long history of stenocardia takes coronarodilator agents. He has also been administered acetylsalicylic acid to reduce platelet aggregation. What is the mechanism of antiplatelet action of acetylsalicylic acid?

Explanation

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Acetylsalicyclic acid (Aspirin) is an NSAID. Cycloxygenase, the enzyme which converts arachidonic acid into the endoperoxide precursors of prostaglandin, has at least two different  isoforms: COX-1 & COX-2. COX-1 is primarily expressed in non-inflammatory cells whereas COX-2 is expressed in activated lymphocytes, polymorphonuclear cells and other inflammatory cells. Acetylsalicyclic acid and the older non-selective NSAIDs inhibit both cyclooxygenase isoforms & thereby decrease prostaglandin & thromboxane synthesis (disaggregating effect) throughout the body.

131.

Pterin derivatives (aminopterin and methotrexate) are the inhibitors of dihydrofolate reductase, so that they inhibit the regeneration of  tetrahydrofolic acid from dihydrofolate. These drugs inhibit the intermolecular transfer of monocarbon groups, thus suppressing the synthesis of the following polymer:

Explanation

Pterin derivatives (aminopterin & methotrexate) are folic acid analogs that inhibit the reduction of dihydrofolate to tetrahydrofolate, catalyzed by dihydrofolate reductase. IMG_9914 These drugs limit the amount of tetrahydrofolate available for use in purine synthesis & this slows down DNA replication (reduction in dTMP) in mammalian cells. These compounds are therefore,useful in treating rapidly growing cancers,but are also toxic to all dividing cells.
132.

A 60-year-old male patient has a 9-year history of diabetes and takes insulin Semilente for the correction of hyperglycemia.10 days ago he began  taking   anaprilin for hypertension.One  hour after administration of the  antihypertensive drug  the patient  developed  hypoglycemic coma. What  is the  mechanism  of hypoglycemia in the case of anaprilin use?

Explanation

Anaprilin is a beta-blocker. It will inhibit epinephrine effect together with glucagon. Epinephrine normally breaks down glycogen (glycogenolysis) to glucose and this makes glycogen available for use in the body. Since Anaprilin inhibits  epinephrine  effect, it therefore inhibits glycogenolysis. Insulin also is a strong inhibitor of glycogenolysis. Therefore, the combination of both Insulin and Anaprilin can lead to hypoglycemic coma.
133.

A patient diagnosed  with focal tuberculosis of the upper  lobe of the right lung had  been  taking  isoniazid  as a part of combination therapy. After  some time, the patient reported of muscle weakness, decreased  skin  sensitivity,   blurred  vision,  impaired  motor   coordination.  Which vitamin  preparation should  be used to address  these phenomena?

Explanation

Isoniazid is the hydrazide of isonicotinic acid and is a pyridine. Pyridine occurs in many important compounds including  azines and the Vitamins Niacin(B3) and Pyridoxine(B6). Therefore, isoniazid can be interfered with Vit.B3, B6 and even B1 metabolism by competing with them.

Isoniazid is a first line antituberculosis drug that inhibits the synthesis of mycolic acid. Vit B6 is needed for the transformation of tryptophan to Vit.B3.

Adverse reaction of Isoniazid: peripheral neuritis, optic neuritis, hepatitis and idiosyncratic hepatotoxicity.
134. The  secretion  of  which  hypophysial hormones will be  inhibited after  taking the  oral contraceptives containing sex hormones?

Explanation

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 Follicle stimulating hormone and the luteinizing hormone are together called gonadotropic hormones or gonadotropins because of their action on gonads. Products containing a combination of an estrogen and a progestin are the most common type of oral contraceptives. The estrogen provides a negative feedback on the release of luteinizing hormone (LH) and follicle stimulating hormone (FSH) by the pituitary gland, thus preventing ovulation. The progestin also inhibits LH release and thickens the cervical mucus, thus hampering the transport of sperm. Oral contraceptives are the drugs taken orally (by mouth) to prevent pregnancy.

135.

A patient has been  given high doses of hydrocortisone for a long time. This caused   atrophy  of  one   of  the   adrenal cortex zones. Which zone is it?

Explanation

The adrenal gland (suprarenal gland) has a secretory parenchymal tissue organized into cortical and medullary regions. Adrenal cortex (derived from mesoderm; steroid-secreting portion) and medulla (derived from neural crest; catecholamine-secreting portion). The adrenal cortex is divided into 3 zones on the basis of arrangement of its cells:

* Zona glomerulosa (15%): arranged in closely packed ovoid clusters; secretes aldosterone.

* Zona fasciculata (80%): large and polyhedral; arranged in long straight cords; secretes cortisol.

* Zona reticularis (5-7%): cells are arranged in anastomosing cords separated by fenestrated capillaries; secretes androgens.

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Hydrocortisone is a glucocorticoid (cortisol) and an intake of hydrocortisone will decrease endogenous production of cortisol from zona fasciculata of adrenal cortex through feedback inhibition leading to its atrophy.

136. A  doctor  recommends a  patient with  duodenal ulcer  to  drink  cabbage  and potato  juice   after   the   therapy  course. Which substances  contained in these vegetables  help  to  heal  and  prevent the ulcers?

Explanation

     Cabbage juice is one of the most healing nutrients for ulcer repair as it is a huge source of vitamin U (vitamin U is actually not a vitamin but an enzyme known as S-methylmethionine). Research shows that vitamin U, administered as raw cabbage juice, is effective in promoting the rapid healing of peptic ulcers. Potatoes on the other hand are rich sources of vitamins and minerals. Several studies, such as the one published in the June 2008 edition of the “Journal of vascular nursing”, have shown reduced levels of vitamin A in patients suffering from leg ulcers, indicating a connection between the two, probably because vitamin A helps to form and maintain healthy skin, mucous membrane and teeth. Vitamin A and the amino acid glutamine help to regenerate healthy epithelial cells.

137.

A  patient suffering  from  myasthenia has been  administered proserin. After  its administration the patient has got nausea, diarrhea, twitch  of  tongue   and  skeletal muscles. What  drug  would  help to eliminate the intoxication?

Explanation

     Neostigmine/proserin reversibly inhibits anticholinesterase, an indirect acting cholinergic agonists. It is used symptomatically to treat myasthenia gravis. Proserin does not cause CNS side effects and is not used to overcome toxicity of central acting antimuscarinic agents.

Atropine is an antimuscarinic agent and is used for the treatment of overdoses or intoxication of cholinesterase inhibitor (proserin, physostigmine) and some types of mushroom poisoning (certain mushrooms contain cholinergic substances that block cholinesterases). It also blocks the effects of excess acetylcholine resulting from acetylcholinesterase inhibitors.

Physostigmine and pyridostigmine bromide are acetylcholinesterase inhibitors and will further synergize proserine.

Mesaton is an α-adrenergic agonists (adrenomimetics); Isadrin is a β-adrenergic agonists.

138. Proserin increases skeletal muscle tone when given systematically. Halothane induces   relaxation  of  skeletal   muscles and   reduces   proserin  effects.   What   is the nature of proserin and halothane interaction?

Explanation

     Proserin (Neostigmine) is an indirect acting cholinergic agonist (anticholinesterase). It preserves endogenous acetylcholine which can stimulate a greater number of acetylcholine receptors at the muscle endplate. Halothane, on the other hand, is a general anesthetic that breaks neurotransmission. Proserin stimulates and aids neurotransmission, while halothane breaks neurotransmission (antagonism). This is done indirectly because they don’t act by the same mechanism to antagonize each other. It is functional because each drug weakens the other’s action/effect.

139. A patient suffering from stomach ulcer has  been   treated with  an  antacid   drug almagel. For acute bronchitis treatment he was prescribed the  antibiotic methacycline.   However    within   next   5  days   the fever   didn’t   fall,   cough    and    sputum nature  remained unchanged. A  physician came to the  conclusion  that  the  drugs were incompatible. What type of drug incompatibility is the case?

Explanation

     Pharmacokinetics refers to what the body does to a drug. Once a drug is administered through one of several available routes, 4 pharmacokinetic properties determine the speed of onset of drug action, intensity of the drug’s effect and the duration of drug action: absorption, distribution, metabolism and elimination.

Absorption: first, drug absorption from the site of administration permits entry of the therapeutic agent (either directly or indirectly) into plasma. Absorption is the transfer of a drug from its site of administration to the bloodstream via different mechanisms.

Methacycline is a tetracycline. All tetracyclines are adequately absorbed after oral ingestion. However, taking these drugs concomitantly with diary foods in the diet decreases absorption due to the formation of nonabsorbable chelates of the tetracyclines with calcium ions. Nonabsorbable chelates are also formed with other divalent and trivalent cations e.g. those found in magnesium and aluminum antacids and in iron preparations. This presents a problem if a patient self-treats the epigastric upsets caused by tetracycline ingestion with antacids.

Nonforming CO2 antacids: aluminum hydroxide + magnesium hydroxide = Almagel or Maalox.

140. A   30-year-old   patient  complains about   having   abdominal  pain   and   diarrhea for  five  days;  body  temperature rise  up  to  37, 5oC  along  with  chills. The day   before   a   patient  had   been   in   a forest and drunk from an open water reservoir.  Laboratory  analyses   enabled to make the following diagnosis: amebic dysentery. What  is the  drug of choice  for its treatment?

Explanation

Metronidazole forms toxic free radical metabolites in the bacterial cell that damage DNA. It is bactericidal, and an antiprotozoal. It is used to treat Giardia, Entamoeba, Trichomonas, Gardnerella vaginalis, Anaerobes (bacteroides, Clostridium difficile). Entamoeba histolytica causes amebic dysentery.

It can be used with a proton pump inhibitor and clarithromycin for “triple therapy” against Helicobacter pylori.

 

141.

Pharmacological effects of anti- depressants are based upon blocking (inhibiting)  the   enzyme   that   acts  as  a catalyst for the breakdown of biogenic amines noradrenalin and serotonin in the mitochondria of cephalic  neurons. What enzyme takes part in this process?

Explanation

Norepinephrine (noradrenaline), epinephrine (adrenaline) and dopamine are catecholamines produced in chromaffin cells of adrenal medulla from tyrosine.

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The catecholamines are inactivated by oxidative deamination catalyzed by monoamine oxidase (MAO) and by O-methylation carried out by Catechol-O-methyltransferase.

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The metabolic products of these reactions are excreted in the urine as vanillymandelic acid from epinephrine and norepinephrine; and homovanillic acid from dopamine.

142. A patient with diabetes mellitus complicated by angiopathy has been recommended a drug which is a sulphonyl urease   derivate of  the  second  generation. It improves microcirculation and is known for its relatively good tolerance. What drug is it?

Explanation

Sulfonylurea are insulin secretagogues because they promote insulin release from the β-cells of the pancreas. The primary drugs used today are the 2nd generation drugs – glibenclamide, glipizide, glimepiride, glibutide etc. These agents are useful in the treatment of patients who have type 2 diabetes mellitus and cannot be managed by diet alone.   Glibenclamide is much more potent and used commonly.

Acarbose – α glucosidase inhibitor.  Actrapid (soluble insulin) is fast acting but not a sulfonylurea.

143. A  patient  presents with  dysfunction of cerebral cortex accompanied by epileptic  seizures.  He  has  been  administered  a biogenic amine  synthesized from glutamate and responsible for central inhibition.  What substance  is it?

Explanation

     Certain amino acids undergo decarboxylation that means the removal of their α-carboxyl group resulting in liberation of CO2 and formation of biogenic amines. Biogenic amines are physiologically active substances such as hormones, neurotransmitters etc. decarboxylation of amino acids:

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·        Tryptophan → Niacin → NAD+/NADP+

Tryptophan → Serotonin →Melatonin

·        Histidine → Histamine

·        Glutamine → GABA

Glutamine → Glutathione

144.

For  relief  of  hypertensive  crisis  a doctor   administered  a   patient  a   drug that   apart   from  antihypertensive  effect has also sedative, spasmolytic and anti-convulsive effect. The drug was taken parenterally. When  it  is  taken   enterally it acts as a laxative and cholagogue.  What drug was administered?

Explanation

Allochol and cholenzyme are agents of biliary acids and bile (cholesecretics – induce bile secretion). Cholosas is a plant agent (cholesecretics – induce bile secretion). Nicodinum is a synthetic agent (cholesecretics – induce bile secretion). They all stimulate bile formation. Magnesium sulfate is a drug causing gall bladder contraction and relaxation of sphincter of oddi; it promotes bile excretion. It is also a salt laxative acting on all intestine’s secretions. It is a non-absorbable salt that hold water in the intestine by osmosis and distend the bowel, increasing intestinal activity and producing defecation.

145. A man was intoxicated with mushrooms. They contain  muscarine  that stimulates muscarinic cholinoreceptors. What symptoms  signalize intoxication with inedible mushrooms?

Explanation

Muscarinic receptors belong to the class of G protein-coupled receptors (parasympathetic nervous system). These receptors, in addition to binding Acetylcholine, it also recognizes muscarine – an alkaloid that is present in certain poisonous mushrooms.

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Muscarinic effects include miosis, spasm of accommodation, increasing of lacrimal, salivary, gastrointestinal, bronchial and sweat glands secretion, increase of smooth muscle tonus of internal organs, bradycardia, decreased arterial pressure.

All other options are sympathetic effects (acting through α or β-adrenergic receptors).

146. A patient with ischemic heart disease has   been   administered  an   anti-anginal drug that  reduces  the myocardial  oxygen consumption and  improves  blood  supply of myocardium. What drug is it?

Explanation

Nitroglycerine is an organic nitrate. By dephosphorylation of myosin chain; it reduces myocardial contractions → decreased myocardial O2 consumption; relaxation of vascular smooth muscle → ↑perfusion → improves blood supply to myocardium.

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   Administered nitrates → ↑ Nitrites →↑ Nitric oxide (NO) → ↑cGMP → ↑dephosphorylation of myosin chains → vascular smooth muscle relaxation. Nitroglycerin is an organic nitrates. Nitrates inhibit coronary vasoconstriction or spasm, increasing perfusion of the myocardium and thus relieving vasospastic angina. Because of this action, nitrates are effective in treating effort-induced (stress) angina. Classic, effort-induced or stable angina are experienced in such conditions as physical activity, emotional excitement or any other cause of increased cardiac workload.

147.

A  patient has  been  diagnosed  with transmural  myocardial   infarction.   What drug should  be given in order  to prevent cardiogenic  shock?

Explanation

 Promedol remains the best answer because it has a spasmolytic  (antispasmodic) and analgesic effect. Therefore, it is very effective for pains associated with spasms of smooth muscles of internal organs and blood vessels. In comparison with morphine hydrochloride, it has less oppressing activity on respiratory centers, less than excites the center of the vagus nerve and the vomiting center. When the pain is associated with spasms of smooth muscle (angina pectoris, liver, kidney, intestinal cramps) you can assign promedol with atropine, metacin, papaverine etc.

148.

A patient suffers from pulmonary tuberculosis. During  treatment neuritis  of visual nerve  arose. What  drug has caused this by-effect?

Explanation

Isoniazid is the hydrazide of isonicotinic acid and is a pyridine. Pyridine occurs in many important compounds including  azines and the Vitamins Niacin(B3) and Pyridoxine(B6). Therefore, isoniazid can be interfered with Vit.B3,B6 and even B1 metabolism by competing with them.

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Isoniazid is a first line antituberculosis drug that inhibits the synthesis of mycolic acid. Vit B6 is needed for the transformation of tryptophan to Vit.B3.

Adverse reaction of Isoniazid: peripheral neuritis, optic neuritis, hepatitis and idiosyncratic hepatotoxicity.
149. A patient suffering from stenocardia was  taking  nitroglycerine which  caused restoration of blood  supply  of myocardium and relieved  pain in the cardiac  area. What intracellular mechanism  provides restoration of  energy  supply  of  insulted cells?

Explanation

Energy supply to any cell is provided by ATP. Nitroglycerine relieves stenocardia by causing vasodilation thereby increasing blood supply locally to the myocardium.

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This increase in blood supply, increases the supply of substrates needed to make ATP. Therefore, a dose of Nitroglycerine → ↑blood supply → ↑substrates for ATP synthesis → ↑intensification of ATP synthesis.

150. A patient consulted  a dentist  about itching and burning in the oral cavity; high temperature. The  patient was diagnosed with trichomonal gingivostomatitis. What drug should be chosen for his treatment?

Explanation

Metronidazole forms toxic free radical metabolites in the bacterial cell that damage DNA. It is bactericidal, and an antiprotozoal. It is used to treat Giardia, Entamoeba, Trichomonas, Gardnerella vaginalis, Anaerobes (bacteroides, Clostridium difficile). It can be used with a proton pump inhibitor and clarithromycin for “triple therapy” against Helicobacter pylori.

151. A patient underwent appendectomy. In the  postoperative period  he has been taking an antibiotic.  The patient complains  about  hearing  impairment and  vestibular disorders.  What group of antibiotics has such by-effects?

Explanation

Aminoglycoside binds the 30S ribosomal subunit and interferes with assembly of the functional ribosomal apparatus and/or can cause the 30S subunit of the completed ribosome to misread the genetic code.

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The elderly are particularly susceptible to nephrotoxicity and ototoxicity as an adverse effect of aminoglycosides. Ototoxicity (vestibular and cochlear) is directly related to high peak plasma levels and the duration of treatment. The antibiotic accumulates in the endolymph and perilymph of the inner ear and toxicity correlates with the number of destroyed hair cells in the organ of corti. Deafness may be irreversible and has been known to affect fetuses in utero.

152.

A 64 year old woman has impairment of twilight vision (hemeralopy). What  vitamin should be recommended in the first place?

Explanation

Vitamin A is the name given to a group of related compounds that include retinol (vitamin A alcohol); retinal (vitamin A aldehyde) and retinoic acid (vitamin A acid). Rod cells are responsible for dim light vision or night vision or scotopic vision.

Rhodopsin or visual purple is the photosensitive pigment of rod cells. It is made up of a protein called opsin and a chromophore. Opsin present in rhodopsin is known as scotopsin. Chromophore is a chemical substance that develops colour in the cell. Chromophore present in the rod cells is called retinal. Retinal is the aldehyde of vitamin A or retinol.

Impairment of twilight vision is a defective function of rod cells. Therefore, vitamin A is recommended as the first choice.

153. A 66 year old female patient got intravenous injection of magnesium sulfate solution for the purpose of elimination of hypertensive crisis. But arterial  pressure didn’t go down and after repeated introduction of  the  same preparation there  appeared sluggishness, slow response, inhibition  of consciousness and respiration. What preparation is antagonist of magnesium sulfate and can eliminate symptoms of its overdose?

Explanation

Magnesium sulfate reduces striated muscle contractions and blocks peripheral neuromuscular transmission by reducing acetylcholine release at the neuromuscular junction. Magnesium is a unique calcium antagonist as it can act on most types of calcium channels in vascular smooth muscle and as such would be expected to decrease intracellular calcium. One major effect of decreased intracellular calcium would be inactivation of calmodulin-dependent myosin light chain kinase activity and decreased contraction, causing arterial relaxation that may subsequently lower peripheral and cerebral vascular resistance, relieve vasospasm and decrease arterial blood pressure. Therefore, it is recommended that intravenous calcium gluconate or calcium chloride should be available as an antagonist of magnesium to increase intracellular calcium level.

154. A  patient suffers  from  stenocardia and takes isosorbide  mononitrate. He was prescribed a complementary drug with disaggregating  effect. What drug is it?

Explanation

Acetylsalicyclic acid (Aspirin) is an NSAID.

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Cycloxygenase, the enzyme which converts arachidonic acid into the endoperoxide precursors of prostaglandin, has at least two different  isoforms: COX-1 & COX-2. COX-1 is primarily expressed in non-inflammatory cells whereas COX-2 is expressed in activated lymphocytes, polymorphonuclear cells and other inflammatory cells.

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Acetylsalicyclic acid and the other non-selective NSAIDs inhibit both cyclooxygenase isoforms & thereby decrease prostaglandin & thromboxane synthesis (disaggregating effect) throughout the body.

155.

A  man  got  poisoned  with mushrooms. They contain  muscarine  that stimulates muscarinic cholinoreceptors. What  symptom   is  typical  for  poisoning with inedible mushrooms?

Explanation

Muscarinic receptors belong to the class of G protein-coupled receptors of the parasympathetic nervous system. These receptors, in addition to binding Acetylcholine, it also recognizes muscarine – an alkaloid that is present in certain poisonous mushrooms.

image

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Muscarinic effects include miosis, spasm of accommodation, increasing of lacrimal, salivary, gastrointestinal, bronchial and sweat glands secretion, increase of smooth muscle tonus of internal organs, bradycardia, decreased arterial pressure.

All other options are sympathetic effects (acting through α or β-adrenergic receptors).

156.

As a result of durative antibiotic therapy a 37 year  old patient developed intestinal  dysbacteriosis.  What   type   of drugs should be used in order  to normalize intestinal microflora?

Explanation

Eubiotics or probiotics aids the development and repopulation of intestinal microbial flora in the event of diarrhea and during treatment with antibiotics and sulfa drugs. A dietary supplement rich in highly concentrated live active cultures contains select high enzymatic function yeast cultures.

157. A patient diagnosed  with morphinism has been  admitted to the narcological department. A  doctor  noted  a  decrease in  pharmacological  activity   of  morphine.  Repetitive use  of  a  drug  may  result in tolerance to its effect, and this phenomenon is called:

Explanation

Morphine is the major analgesic drug contained in crude opium and is the prototype strong agonist. Morphine and several other opoids have high affinity for μ receptors, whereas other agents have varying affinities for δ and κ receptors. Long term chronic administration can result in physical and psychological dependence (addiction). Withdrawal produces a series of autonomic, motor and psychological responses that incapacitate the individual and cause serious (almost unbearable) symptoms. Repeated use produces tolerance to the respiratory depressant, analgesic, euphoric and sedative effects of morphine. Morphinism is excessive or uncontrolled usage of morphine.

158. A patient with epilepsy and depressive reaction has been  administered a drug that  reduced epilepsy  manifestations and improved  the patient’s psychic condition.

Explanation

Natrii valproas (sodium valproate) has antiseizure(antiepileptic) activity. It has proved to be the most effective is seizure states with a subcortical focus (e.g. absence seizures). It has also been effective in grand mal seizures but much less effective in partial seizures. It has anticonvulsant, antidepressant, psychotonic (improves psychic conditions) and cardioprotective effects.

Ethosuxemide and Phenobarbital, phenytoin are antiepileptic but no psychotonic effects. Amitriptyline is an antidepressant.

159.

An elderly patient has chronic constipations induced by large intestine hypotonia. What  drug  should  be administered?

Explanation

Constipations requires the use of laxatives that will stimulate the movement of food through gastrointestinal tract (GIT), produce soft formed stool and accelerate defecation. Bisacodyl is typically prescribed for relief of constipation and for the management of neurogenic bowel dysfunction as well as part of bowel preparation before medical examinations, such as for a colonoscopy. Bisacodyl works directly on the colon to produce bowel movement. It works by stimulating enteric nerves to cause colonic mass movements (contractions); removing the colon hypotonia.

160.

After  4 months  of treatment for tuberculosis the patient began complaining of toes and fingers numbness, sensation of creeps. He was diagnosed with polyneuritis.  What  antituberculous drug might have caused these complications?

Explanation

Isoniazid is the hydrazide of isonicotinic acid and is a pyridine. Pyridine occurs in many important compounds including  azines and the Vitamins Niacin(B3) and Pyridoxine(B6). Therefore, isoniazid can be interfered with Vit.B3,B6 and even B1 metabolism by competing with them.

image

Isoniazid is a first line antituberculosis drug that inhibits the synthesis of mycolic acid. Vit B6 is needed for the transformation of tryptophan to Vit.B3.

Adverse reaction of Isoniazid: peripheral neuritis, optic neuritis, hepatitis and idiosyncratic hepatotoxicity.

The primary adverse effect of isoniazid is peripheral neuritis, manifesting as paresthesias of the hands and feet. This appears to be due to a relative pyridoxine deficiency.

 
161. After  the  second  abortion a 23 year old   woman   has   been   diagnosed    with  toxoplasmosis. Which drug should be used for toxoplasmosis treatment?

Explanation

     Toxoplasma gondi (a protozoa) causes toxoplasmosis, including congenital toxoplasmosis. Tissue cyst (pseudocysts) in undercooked meat or oocyst in cat faeces infects humans. Stages in human most associated with disease includes:

·        Rapidly multiplying trophozoites (tachyzoites) within various cell types.

·        Tachyzoites can pass placenta and infect fetus (congenital toxoplasmosis)

·        Slowly multiplying trophozoites (bradyzoites) in tissue cysts.

Symptomatic and asymptomatic forms of congenital toxoplasmosis should be treated with a combination of sulfadiazine and pyrimethamine/Trimethoprim. Cotrimoxazole is a combination of sulfadiazine + Trimethoprim

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Itraconazole – antifungal; Mebendazole – antihelminthic; Azidothymidine and acyclovir – antiviral.

162.

While  under  barbituric anaesthesia a 65 year old male patient developed respiratory  inhibition.  Anesthesiologist made him a 10 ml intravenous injection  of 0,5% bemegride solution.  The  patient’s  condition  got  better, the  pulmonary ventilation volume  increased.  What  phenomenon underlies the  interaction of  these  medications?

Explanation

     Barbiturates (Phenobarbital, thiopental) are hypnotics, sedative for anxiety, seizures, insomnia, induction of anesthesia and they induce normal sleep. They have narcotic type of action. Any degree of depression of the CNS is possible, depending on the dose.

Bemegride on the other hand is an analeptic. Analeptics are drugs which act upon the CNS general functions, but stimulates mainly medulla oblongata (respiratory, cardiovascular centers). They can be used in stimulation of respiratory in overdosage or poisoning with narcotic drugs (drugs for general anesthesia, barbiturates).

Both drugs act on CNS but with directly opposite (antagonistic) actions and with a direct action.

163. A child suffers from drug idiosyncrasy. What is the cause of such reaction?

Explanation

Hereditary enzymopathy is an inherited inefficiency or lack of enzymes participating in drug metabolism.

Idiosyncrasy and allergic reaction is as a result of organism’s increased sensitivity to the drugs. It’s a complication of pharmacological therapy (adverse reactions). Tolerance and Tachyphylaxis are effects of repeated doses.

* Idiosyncrasy is genetically conditioned perverse organism’s response to drugs (e.g. inefficiency, lack of enzymes participating in drug metabolism). Genetic deficiency of glucose 6-phosphate dehydrogenase (hereditary enzymopathy). This enzyme is needed for proper functioning of glutathione (an antioxidant) to prevent the oxidative effect of antimalarial drugs on the RBCs.

* Allergic reactions results from antibody production against some drugs.

 

164. To prevent postoperative bleeding a 6-year-old child was administered vicasol that  is a synthetic  analogue  of vitamin K . Name post-translational changes of blood coagulation factors  that  will be activated by vicasol:

Explanation

Vitamin K-dependent factors include factor II, VII, IX and X; protein C and S. vitamin K is activated in the liver by epoxide reductase.

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Activated vitamin K ɣ-carboxylates each of the vitamin K-dependent factors. Carboxylated factors are now able to bind calcium, which are essential for interaction between the coagulation factors and platelet membranes.

Factor II – Prothrombin

Factor VII – Stable factor

Factor IX – Christmas factor

Factor X – Stuart-Prower factor

These factors undergo vitamin K-dependent post-translational modification, whereby a number of their glutamic acid residues are carboxylated to form ɣ-carboxyglutamic acid residues. The ɣ-carboxyglutamyl residues bind calcium ions which are essential for interaction between the coagulation factors and platelet membranes.

165.

A patient has a slowly healing fracture. What  medicine  can be used to accelerate formation of connective tissue matrix?

 

Explanation

     Methyluracil is a nonsteroidal anabolic, it can also act as a leucopoiesis stimulator, a non-specific drug which stimulates nucleic acid synthesis and proteins sufficient for leucopoiesis and other regeneration processes. Uses – radiation skin damages, fractures, slow recovering burns, agranulocytosis and leucopenia.

Cyclophosphan and Methotrexate are anticancer drugs (cytostatics)

Prednisolone (glucocorticoids) and cyclosporine are immunosuppressants.

166.

A nurse  accidentally  injected  a nearly double dose of insulin to a patient with diabetes  mellitus. The patient lapsed  into a hypoglycemic coma. What drug should be injected in order to help him out of coma?

Explanation

     Hypoglycemic coma is an acute condition progressing during rapid reduction of glucose level in blood and abrupt lowering of glucose utilization by brain. Overdosage of insulin is the most common cause; other causes are alcohol, overdose of oral hypoglycemic agents, insulinoma etc.

Treatment: for correction of hypoglycemia

20.0-60.0ml of 40% solution glucose intravenously (IV)

500ml of 5% solution glucose IV drip feed; or

Subcutaneous injection of glucagon 1.0ml

Subcutaneous injection of 1.0ml – 0.1% adrenaline (epinephrine)

167.

A   patient has myocardial   infarction  with  thrombosis of  the  left  coronary artery. What pharmacological preparation group should be used to reestablish blood flow?

Explanation

     The thrombosis in the left coronary artery has probably led to the development of myocardial infarction. Therefore, the best action to take to reestablish blood flow is to break up the thrombus.

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To achieve this, we need a fibrinolytic (thrombolytic) – which are used for dissolution of the blood thrombi by stimulating natural fibrinolytic system (activation of plasminogen to active plasmin which degrades fibrin).

168.

A 20 year old patient complains of morbid thirst and hyperdiuresis (up to 10 l daily). Glucose concentration in blood is normal but it is absent in urine. The patient has been diagnosed with diabetes insipidus.  What hormonal drug is the most appropriate for management of this disorder?

Explanation

     Diabetes insipidus (D.I.) is characterized by intense thirst and polyuria (hyperdiuresis) with inability to concentrate urine due to lack of ADH (central D.I.) or failure of response to circulating ADH (nephrogenic D.I.). In central D.I. antidiuretic hormone (ADH) is decreased; in nephrogenic D.I. ADH is normal. Therefore, the hormonal drug we can use to treat diabetes insipidus is to replace the low antidiuretic hormone (ADH) in central diabetes insipidus.

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So, we use ADH – a posterior pituitary hormone which increases water reabsorption in renal tubules and decrease diuresis. Its analogue desmopressin acetate can also be administered intranasally. Nephrogenic diabetes insipidus does not require hormonal replacement.

169. A  65 year  old  patient with  chronic heart  failure  has been  taking  digitoxin  in self-administered dosages  for  a  long  time. She was admitted to the hospital for general health aggravation, arrhythmia, nausea,  reduced diuresis, insomnia.  What is the primary action to be taken?

Explanation

     Digitoxin is a long acting cardiac glycoside; used to treat chronic heart failure I-IIB stages, supraventricular tachyarrhythmia (fibrillation, Wolff-Parkinson-White syndrome). Since the patient has been taking this drug in  self-administered doses, there is a high probability of taking an overdosage which can result in toxic concentrations and at toxic concentrations, it causes ectopic ventricular beats that may result in ventricular tachycardia and fibrillation (arrhythmia). This arrhythmia is usually treated with lidocaine or phenytoin but in the absence of this, the first action to take is to stop taking the drug completely (to withhold digitoxin).

170.

A patient suffering from syphilis has been  treated with  bismuth  preparations. As  a result  of it some  grey spots  turned up on the  mucous  membrane of the  oral cavity; nephropathy symptoms  were  also present. What drug should  be  used  for treatment of bismuth intoxication?

Explanation

Dimercaprol (unithiol, British anti-lewisite) is used to chelate mercury, bismuth, arsenic and in combination with edentate calcium disodium to treat lead intoxication. It contains two sulfuhydryl (SH-) groups and forms two bonds with metal ions. Administered intramuscularly.

 

171. A patient suffering from chronic hyperacidic    gastritis   takes    an   antacid drug for heartburn elimination. After its ingestion the patient feels better but at the same time he has a sensation of stomach swelling. Which of the following drugs might be the cause of such side effect?

Explanation

     Antacids are weak bases that react with gastric acid to form water and a salt to diminish gastric acidity. Because pepsin is inactive at a pH greater than 4, antacids also reduce pepsin activity. They can be:

·        CO2 forming: sodium hydrocarbonate (or carbonate); calcium carbonate

·        Non-forming CO2: magnesium hydroxide, aluminum hydroxide

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Uses: hyperacid gastritis, gastric and duodenal ulcers; poisoning with acids.

Adverse effects: in addition to the potential for systemic alkalosis, sodium hydrocarbonate liberates CO2 causing belching and flatulence (sensation of stomach swelling); aluminum hydroxide tends to cause constipation, whereas magnesium hydroxide tends to produce diarrhea.

172.

A 63 year  old  patient with  collapse presentations was delivered to the emergency  hospital.  A physician has chosen noradrenalin against hypotension. What is its mechanism of action?

Explanation

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Because norepinephrine is the neuromediator of adrenergic nerves, it should theoretically stimulate all types of adrenergic receptors. In practice, when the drug is given in therapeutic doses to humans, the α-adrenergic receptor is most affected.

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Norepinephrine causes a rise in peripheral resistance due to intense vasoconstriction of most vascular beds, including the kidney (α1 effect). Both systolic and diastolic blood pressures increase. α1 receptors are present on the postsynaptic membrane of the effector organs and mediate constriction of smooth muscle. NB: norepinephrine (noradrenaline) causes greater vasoconstriction than epinephrine, because it does not induce compensatory vasodilation via β2 receptors on blood vessels supplying skeletal muscles.

173. A 5 year old child has been diagnosed with acute right distal pneumonia. Sputum inoculation revealed that the causative agent  is resistant  to  penicillin, but it is sensitive to macrolides.  What drug should be prescribed?

Explanation

     Macrolides inhibit protein synthesis by blocking translocation, they bind to the 23S rRNA of the 50S ribosomal subunit. It is bacteriostatic. Examples of macrolides includes azithromycin, clarithromycin, erythromycin etc.

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All other options are not macrolides, but are antibiotics.

Ampicillin is an extended spectrum penicillin; a β-lactam antibiotic.

Gentamycin and streptomycin are Aminoglycosides. Together with tetracyclines, they are 30S ribosomal subunit inhibitor.

174.

Bacterioscopic examination of a smear from the  pharynx  of a diphtheria suspect revealed   bacilli  with  volutine   granules. What etiotropic drug  should  be  chosen in this case?

Explanation

     Etiotropic drug deals directly with the etiological factor (diphtheria toxin). Antidiphtheric antitoxic serum neutralizes the toxin of diphtheria and is employed both as a curative and as a prophylactic agent. Diphtheric anatoxin (diphtheria toxoid) is the diphtheria toxin that has been weakened until it is no longer toxic but is strong enough to induce the formation of antibodies and immunity to the disease.

175. After implantation of a cardiac valve a young man constantly takes  indirect  anti-coagulants.  His state was complicated by  hemorrhage. What  substance  content has decreased in blood?

Explanation

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 Indirect anticoagulants:

·        Coumarine derivatives – Neodicumarin, warfarin, syncumar

·        Indandione derivatives – Phenylinum

They antagonize the cofactor functions of vitamin K. Vitamin K is essential for the formation of various clotting factors in the liver, namely clotting factor II, VII, IX and X; Protein C and S.

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Factor II – Prothrombin

Factor VII – Stable factor

Factor IX – Christmas factor

Factor X – Stuart-Prower factor

These factors undergo vitamin K-dependent post-translational modification, whereby a number of their glutamic acid residues are carboxylated to form ɣ-carboxyglutamic acid residues. The ɣ-carboxyglutamyl residues bind calcium ions which are essential for interaction between the coagulation factors and platelet membranes. This oral anticoagulants block epoxide reductase and creation of active form of vitamin K resulting in disturbances in prothrombin and proconvertin synthesis in liver.

All other options are not clotting factors.

176.

Examination  of  a  child  who  hasn’t got fresh  fruit  and  vegetables  during  winter revealed numerous subcutaneous hemorrhages, gingivitis, carious cavities in teeth.  What vitamin combination should be prescribed in this case?

Explanation

Vitamin P (rutin) – permeability vitamin. They reduce permeability of blood vessels, especially capillaries. It prevents hyaluronic acid (the basic compound of the extracellular matrix) from degeneration by inhibition of the enzyme hyaluronidase. Ascorutin is a drug containing vitamin C and P; it is used to decrease the permeability of blood vessels.

Vitamin C (ascorbic acid): found in fruits and vegetables; an antioxidant; also facilitates iron absorption by reducing it to Fe2+ state. It is necessary for hydroxylation of proline and lysine in collagen synthesis; necessary for dopamine β-hydroxylase, which converts dopamine to norepinephrine. Deficiency leads to: scurvy – swollen gums, bruising, petechiae, hemarthrosis, anemia, poor wound healing, perifollicular and subperiosteal hemorrhages, “corkscrew” hair; Weakened immune response.

Type III collagen is found in blood vessels; Type IV collagen is found in basement membrane. Deficiency in Vitamin C disrupts the second stage of collagen synthesis in fibroblasts (hydroxylation of collagen) which results in petechiae, bruising, hemarthrosis.

Vitamin B2 (riboflavin) deficiency – growth retardation, glossitis, conjunctivitis

Vitamin B1 (thiamine) deficiency – Beri-Beri (polyneuritis)

Vitamin A (retinol) deficiency – Night blindness

Vitamin B9 (folic acid) deficiency – macrocytic megaloblastic anemia

177.

During  an operation a patient got injection  of  muscle  relaxant dithylinum. Relaxation of skeletal  muscles and inhibition of respiration lasted  two hours.  This condition was caused  by absence  of the following enzyme in blood serum:

Explanation

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Dithyllium is a depolarizing myorelaxant (neuromuscular blocking drug). They are used as adjuvant drugs in anaesthesia during surgery to relax skeletal muscles.

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An absence or deficiency of acetylcholinesterase/pseudocholinesterase enzyme leads to a silent condition that manifests itself only when people that have the deficiency receive the muscle relaxants. This enzyme plays an important role in  the metabolism of ester-based local anesthesics, a deficiency of blood cholinesterase can prolong the effect of dithylinium from just 5-7minutes to 8hours.

[Wherever Butyrylcholinesterase occurs in the option along with Acetylcholinesterase; butyrylcholinesterase is the right option in krok]