Endocrine Pharmacology USMLE Step 1 Practice Question
A 70-year-old man with small cell lung carcinoma presents with severe headache and confusion. Vital signs show BP 128/76 mmHg, HR 88/min, RR 16/min, temperature 37.2°C. Laboratory studies reveal serum sodium 118 mEq/L, serum osmolality 245 mOsm/kg, and urine osmolality 650 mOsm/kg. Chest imaging confirms malignancy. He denies recent diuretic use. A selective V2 receptor antagonist is initiated for symptomatic SIADH. Which drug was most likely prescribed?
Answer choices
- ADemeclocycline
- BFludrocortisone
- COxytocin
- DTolvaptanCorrect answer
- EDesmopressin
- FLithium carbonate
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