Endocrine Pharmacology USMLE Step 1 Practice Question
A 42-year-old woman with refractory Graves disease on propylthiouracil presents for preoperative optimization before scheduled thyroidectomy in 10 days. Vital signs: BP 142/88, HR 108, RR 20, Temp 37.2°C. Labs show TSH <0.01 mIU/L, free T4 8.2 ng/dL, and an elevated radioactive iodine uptake of 72%. Physical exam reveals a thyroid bruit and a diffusely enlarged, hypervascular gland on ultrasound but no exophthalmos. To acutely inhibit thyroid hormone release and decrease gland vascularity before surgery, an additional drug is started. Which agent was most likely added?
Answer choices
- ARadioactive iodine
- BPropylthiouracil
- CLevothyroxine
- DPotassium iodideCorrect answer
- EMethimazole
- FPropranolol
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