Endocrine Pharmacology USMLE Step 1 Practice Question
A 26-year-old woman at 8 weeks' gestation presents with thyroid tenderness, heat intolerance, and palpitations. Vital signs show BP 138/82 mmHg, HR 108/min, RR 18/min, and temperature 37.2°C. TSH is suppressed at 0.1 mIU/L with elevated free T4 of 2.8 ng/dL. Thyroid ultrasound demonstrates diffuse enlargement without nodules. She denies recent iodine exposure. Because of her pregnancy timing, her physician prescribes a thionamide that inhibits both thyroid peroxidase and peripheral T4-to-T3 conversion. Which drug was most likely prescribed?
Answer choices
- ARadioactive iodine
- BPropranolol
- CPropylthiouracilCorrect answer
- DMethimazole
- EPotassium iodide
- FLevothyroxine
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