A 24-year-old woman with polycystic ovary syndrome complains of moderate hirsutism. She is started on spironolactone. Its antiandrogen effect in hirsutism is primarily due to:

• A Inhibition of 5-alpha reductase
• B Suppression of ovarian androgen production
• C Blockade of androgen receptors ✓
• D Increased hepatic synthesis of sex hormone-binding globulin

Explanation

Spironolactone is a competitive antagonist of the androgen receptor, which is the primary mechanism for its benefit in hirsutism. Finasteride inhibits 5-alpha reductase. Combined oral contraceptives suppress ovarian androgen production. Estrogens increase hepatic SHBG synthesis, not spironolactone.

Reference: Katzung Basic and Clinical Pharmacology, 15th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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