Pharmacology Flashcards
6 cards from real COMLEX-USA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Pharmacology flashcards as text
Which beta-blocker is cardioselective (beta-1 selective) and commonly used in heart failure?
Answer: Metoprolol succinate
Metoprolol succinate (extended-release) is a beta-1 selective blocker proven to reduce mortality in heart failure with reduced ejection fraction.
The mechanism of action of metformin in type 2 diabetes primarily involves:
Answer: Activating AMPK to reduce hepatic gluconeogenesis
Metformin activates AMPK, which decreases hepatic gluconeogenesis and increases peripheral insulin sensitivity without causing hypoglycemia.
A patient taking warfarin is started on trimethoprim-sulfamethoxazole for a UTI. Which effect is expected?
Answer: Increased anticoagulation due to CYP2C9 inhibition
TMP-SMX inhibits CYP2C9, which metabolizes S-warfarin, leading to increased warfarin levels and elevated INR/bleeding risk.
Which opioid analgesic is contraindicated in patients with renal failure due to accumulation of its active metabolite morphine-6-glucuronide?
Answer: Morphine
Morphine's active metabolite morphine-6-glucuronide (M6G) accumulates in renal failure, causing prolonged sedation and respiratory depression.
Atropine reverses bradycardia caused by organophosphate poisoning by which mechanism?
Answer: Competitively blocking muscarinic receptors
Atropine competitively antagonizes muscarinic acetylcholine receptors, reversing the excess cholinergic (SLUDGE) effects of organophosphate poisoning.
Which class of antibiotics inhibits bacterial cell wall synthesis by binding to PBPs and is bactericidal?
Answer: Beta-lactams
Beta-lactam antibiotics (penicillins, cephalosporins, carbapenems) bind penicillin-binding proteins (PBPs) to inhibit cell wall cross-linking, causing bacterial lysis.