A 55-year-old on quinidine develops QT prolongation and torsades de pointes. Which electrolyte abnormality likely contributed? 

A 52-year-old man with severe alcohol use disorder is interested in medication-assisted treatment after completing inpatient detoxification. He has normal renal function. He expresses strong motivation to remain abstinent but admits that cravings are high when he is around friends who drink. He wants “something that will stop me from drinking if I slip.” Which pharmacologic agent is most appropriate for this treatment goal? 

Which antiarrhythmic is safest for atrial fibrillation in HFrEF? 

A 71-year-old man with HFrEF presents with nausea, yellow-green visual halos, and new-onset ventricular ectopy. He has been compliant with his digoxin therapy and recently had his furosemide dose increased for volume overload. Labs: K⁺ = 2.8 mEq/L, Cr = 1.0 mg/dL. Which factor most likely precipitated his digoxin toxicity? 

A 74-year-old man with ischemic cardiomyopathy and chronic atrial fibrillation presents to clinic with complaints of fatigue, anorexia, and intermittent visual blurring. He takes digoxin, furosemide, lisinopril, and warfarin. Exam: HR 48 bpm, irregular; BP 102/60 mmHg. Labs: K⁺ = 2.7 mEq/L, Cr = 1.0 mg/dL. Which medication combination most likely precipitated this presentation? 

Which drug is most appropriate for managing tremor-predominant Parkinson’s in a younger patient? 

A 48-year-old man with a 30–pack-year smoking history presents for help with quitting. He has no history of depression, seizures, or cardiovascular disease. He has attempted to quit twice in the past using willpower alone but relapsed within weeks due to strong cravings. He expresses high motivation to stop now, stating, “I’ll try whatever works best.” Which first-line pharmacologic intervention is most appropriate to recommend? 

A 64-year-old woman is hospitalized for pneumonia and has been receiving broad-spectrum antibiotics (cefepime and vancomycin) for 10 days. She now reports profuse watery diarrhea (8 stools/day), abdominal cramping, and low-grade fever. Vitals: T 100.9°F, BP 106/68, HR 102. Labs: WBC 15,000/µL, creatinine 1.8 mg/dL (baseline 0.9). Stool is heme-negative. Which diagnosis is of greatest concern?

A patient with moderate Alzheimer’s is prescribed memantine. Its mechanism is: 

A 64-year-old man with known coronary artery disease (CAD) is treated with isoproterenol, a nonselective beta agonist, for evaluation of cardiac conduction. Shortly after infusion begins, he develops palpitations and chest discomfort. Which adverse effect is the greatest concern in this patient?