Endocrine Pharmacology USMLE Step 1 Practice Question
A 39-year-old woman with Cushing disease presents for pituitary ACTH reserve testing. Vital signs show BP 158/92 mmHg, HR 88, RR 16, temp 37°C. Physical examination reveals central obesity and purple abdominal striae. She reports no current headaches. Laboratory studies reveal elevated 24-hour urinary cortisol at 285 mcg/24h and elevated ACTH at 62 pg/mL. A drug inhibiting 11β-hydroxylase is administered orally at midnight, causing cortisol levels to decrease and 11-deoxycortisol to increase, confirming intact pituitary ACTH secretion. Which medication was most likely given?
Answer choices
- AFludrocortisone
- BRadioactive iodine
- CKetoconazole
- DMetyraponeCorrect answer
- EHydrocortisone
- FMitotane
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