Thyroid Disorders USMLE Step 1 Practice Question
A 35-year-old woman at 12 weeks gestation presents with thyroid eye disease, tremor, and palpitations. Vital signs show HR 102 bpm, BP 138/88 mmHg, RR 18, temp 37.2°C. Labs reveal suppressed TSH 0.1 mIU/L, elevated free T4 2.5 ng/dL, and positive TSH receptor antibodies. She denies recent iodine exposure. Which antithyroid agent carries the lowest risk of congenital anomalies during the first trimester?
Answer choices
- AIodine solution (Lugol or SSKI)
- BMethimazole
- CPropranolol alone
- DAtenolol alone
- EPropylthiouracilCorrect answer
- FLevothyroxine monotherapy
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