PTCB Pharmacology #5 3

Question 1

Which drug is the antidote for heparin overdose?

Accepted Answer

Protamine sulfate

Answer

Protamine sulfate reverses unfractionated heparin toxicity. It is a positively charged protein that binds the negatively charged heparin, forming a stable complex that neutralizes anticoagulant activity.

Question 2

Which class of drug do "-zosin" suffix drugs (e.g., tamsulosin, doxazosin) belong to?

Accepted Answer

Alpha-1 adrenergic blockers

Answer

Alpha-1 blockers end in "-zosin" (tamsulosin, doxazosin, prazosin, terazosin). They relax smooth muscle in blood vessels and the prostate/bladder neck, used for hypertension and BPH.

Question 3

Varenicline (Chantix) is used for smoking cessation because it:

Accepted Answer

Partially activates nicotinic acetylcholine receptors while blocking nicotine binding

Answer

Varenicline is a partial agonist at alpha4-beta2 nicotinic acetylcholine receptors. It provides mild dopamine release (reducing cravings/withdrawal) while blocking nicotine's full receptor activation (reducing reinforcement from smoking).

Question 4

Drug-induced lupus (DIL) is most commonly associated with which drug?

Accepted Answer

Hydralazine

Answer

Hydralazine, procainamide, and isoniazid are the classic drugs most commonly causing drug-induced lupus. The syndrome typically resolves upon drug discontinuation.

Question 5

Which of the following is the primary reason why grapefruit juice interacts with simvastatin?

Accepted Answer

It inhibits intestinal CYP3A4, increasing simvastatin bioavailability and myopathy risk

Answer

Grapefruit juice inhibits CYP3A4 in the intestinal wall (irreversibly), dramatically increasing simvastatin bioavailability. This raises plasma levels significantly, increasing the risk of myopathy and rhabdomyolysis.

Pharmacy Practice Test

Pharmacy Practice Test

PTCB Pharmacology #5 3