Cardiovascular Drugs USMLE Step 1 Practice Question
A 52-year-old woman with atrial fibrillation for 2 years on digoxin presents with nausea, visual disturbances with yellow-green halos, and dizziness. Vital signs: BP 98/62 mmHg, HR 42 bpm, RR 16/min, Temp 37°C. Serum digoxin level is 2.8 ng/mL (therapeutic range 0.8-2.0 ng/mL). ECG shows multiple premature ventricular contractions. Potassium is 3.2 mEq/L. She denies chest pain. Which intervention is most appropriate?
Answer choices
- AIncrease digoxin dose to improve rate control
- BContinue current dose; symptoms are unrelated to digoxin
- CAdd verapamil to enhance negative dromotropic effects
- DReduce digoxin dose; signs suggest toxicity despite therapeutic levelCorrect answer
- EAdminister atropine to reverse bradycardia immediately
- FAdminister digoxin immune Fab (Digibind) to reverse digitalis toxicity
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations — plus adaptive practice that targets your weak areas — with a free MedBoardPRO account.