Practice Test Geeks(PSA) Prescribing Safety Assessment Practice Test
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Adverse Drug Reactions Flashcards

7 cards from real PSA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Adverse Drug Reactions flashcards as text

  1. A patient develops a persistent dry cough 3 weeks after starting ramipril for hypertension. What is the most appropriate management?

    Answer: Switch to an angiotensin receptor blocker

    ACE inhibitor-induced cough is caused by bradykinin accumulation and does not resolve with dose reduction; switching to an ARB avoids bradykinin-related effects entirely.

  2. Metformin should be withheld in patients with an eGFR below which threshold due to the risk of lactic acidosis?

    Answer: 30 mL/min/1.73m²

    Metformin is contraindicated when eGFR falls below 30 mL/min/1.73m² because impaired renal clearance leads to drug accumulation and risk of potentially fatal lactic acidosis.

  3. A patient on simvastatin 40 mg starts clarithromycin for a chest infection and develops severe myalgia with dark urine. What is the most likely mechanism?

    Answer: Clarithromycin inhibits CYP3A4, raising simvastatin plasma levels

    Clarithromycin is a potent CYP3A4 inhibitor that markedly increases simvastatin exposure, precipitating statin-induced myopathy and potentially rhabdomyolysis.

  4. NSAIDs precipitate acute kidney injury primarily through which mechanism?

    Answer: Inhibition of prostaglandin-mediated afferent arteriolar vasodilation

    NSAIDs inhibit prostaglandin synthesis, abolishing the afferent arteriolar vasodilation that maintains glomerular filtration rate when renal perfusion pressure is reduced.

  5. A patient on warfarin has their INR rise from 2.5 to 5.8 after starting trimethoprim for a UTI. What is the primary mechanism of this interaction?

    Answer: Trimethoprim inhibits CYP2C9, reducing S-warfarin metabolism

    Trimethoprim inhibits CYP2C9, the primary enzyme metabolizing the more potent S-warfarin enantiomer, leading to drug accumulation and supratherapeutic anticoagulation.

  6. Which monitoring parameter is most important when prescribing aminoglycosides to prevent nephrotoxicity and ototoxicity?

    Answer: Trough serum levels and renal function

    Aminoglycoside toxicity is concentration-time dependent, with sustained elevated trough levels predicting nephrotoxicity and ototoxicity; dose intervals are adjusted based on trough and eGFR.

  7. Clozapine requires mandatory full blood count monitoring primarily because of which serious adverse drug reaction?

    Answer: Agranulocytosis

    Clozapine causes agranulocytosis in approximately 1% of patients, necessitating weekly FBC monitoring for the first 18 weeks then at minimum every 4 weeks thereafter.