Thyroid Disorders USMLE Step 1 Practice Question
A 27-year-old woman at 8 weeks gestation presents with palpitations, heat intolerance, and weight loss despite increased appetite. Vital signs show HR 108 bpm, BP 138/82 mmHg, 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 gland enlargement with increased vascularity. She denies neck pain. Which medication is preferred during the first trimester because it also decreases peripheral conversion of T4 to T3?
Answer choices
- AMethimazole
- BLevothyroxine
- CPropranolol
- DPropylthiouracilCorrect answer
- ERadioactive iodine
- FAtenolol
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