Thyroid Disorders USMLE Step 1 Practice Question
A 42-year-old woman presents with a 3-month history of fatigue, weight gain, cold intolerance, and constipation. Vital signs show HR 52 bpm, BP 128/82 mmHg, temperature 36.2°C. Physical examination reveals dry skin, bradycardia, and delayed deep tendon reflexes. TSH is elevated at 8.5 mIU/L (normal 0.4-4.0) with free T4 of 0.8 ng/dL (normal 0.8-1.8). She denies recent medication changes. Which of the following is the most appropriate initial treatment?
Answer choices
- ALiothyronine monotherapy
- BLevothyroxine monotherapyCorrect answer
- CLevothyroxine plus liothyronine combination
- DObservation with reassessment in 6 months
- EPropranolol and methimazole
- FIodine supplementation with potassium iodide
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