MDS PREP
A Class III antiarrhythmic agent that blocks K+ channels, prolongs action potential duration , and lengthens QT interval.
1) propranolol
2) acebutolol
3) sotalol
4) esmolol
Pharmacology Answer: 3
Sotalol is a Class III antiarrhythmic agent that blocks K+ channels, prolongs action potential duration (APD), and lengthens QT interval.
Noncardiac selective beta-adrenergic blocker.
The D-isomer has less than 1/50 beta-blocking activity of the L-isomer.
Sotalol possesses 30% of beta-blocking activity of propranolol
Dry mouth during antidepressant therapy is caused by blockade of:
1) Muscarinic acetylcholine receptors.
2) Serotonergic receptors.
3) Dopaminergic receptors.
4) GABA receptors.
Pharmacology Answer: 1
Anticholinergic side effect of antidepressant leads to dry mouth in the patients on these drugs.
Dry mouth is due to the Muscarinic acetylcholine receptor antagonism of these drugs.
Penicillins:
1) Are the antibiotic of choice for anaerobic infections
2) Are bacteriostatic
3) Are protagonistic to tetracycline
4) Interfere with bacterial cell wall synthesis
Pharmacology Answer: 4
The penicillins all act by interfering with bacterial cell wall synthesis, by inhibiting cross-linking of the mucopeptides in the cell wall and as such are bacteriocidal. Bacteria are attacked when cells are dividing and so in theory antibiotics that are bacteriostatic would decrease the efficacy of bacteriocidal drugs. However, this doesn’t often cause a problem but tetracycline and penicillin are antagonistic and should not be used at the same time. Metronidazole is the antibiotic of choice for anaerobic infections.
Which of the following is used in the treatment of meningococcal meningitis in patients allergic to penicillin?
1) Ciprofloxacin
2) Teicoplanin
3) Meropenem
4) Chloramphenicol
Pharmacology Answer: 4
Treatment of meningococcal meningitis:
Drug of choice – Penicillin G
In case of penicillin resistance, third generation cephalosporins should be used ( Ceftriaxone / CefotaximeIn case of penicillin / cephalosporin allergy, Chloramphenicol is used
Which of the following is not a loop diuretic:
1) Fruesmide
2) Torsemide
3) Ethacrynic acid
4) Chlorthalidone
Pharmacology Answer: 4
Chlorthalidone (Thiazide like diuretic)
Which of the following antihypertensive drugs should not be used in a patient on Lithium in order to prevent Lithium Toxicity?
1) Clonidine
2) Beta blockers
3) Calcium Channel Blockers
4) Diuretics
Pharmacology Answer: 4
Diuretics increase sodium loss in urine and increase lithium retention. Hence they should not be used in patients on Lithium.
Which receptors are implicated in anti emetic effects:
1) D2
2) V2
3) MU2
4) GABA
Pharmacology Answer: 2
CTZ rich in D2 and 5HT receptors
Which of following statement about drug action is false ?
1) Competitive antagonist has no intrinsic activity but affinity
2) Competitive antagonist has intrinsic activity and affinity
3) Partial agonist has submaximal intrinsic activity and affinity
4) Inverse agonists have affinity but minus intrinsic activity.
Pharmacology Answer: 2
Competitive antagonists bind to receptors but do not activate them, meaning they have no intrinsic activity. They have affinity for the receptor, allowing them to compete with agonists for binding.