Danazol, used in endometriosis, produces its therapeutic and adverse effects through which characteristic pharmacological profile?

• A Selective oestrogen receptor modulator with agonist action on bone and antagonist action on endometrium
• B GnRH agonist that downregulates pituitary receptors after initial flare
• C Pure progestogen that causes decidualisation and atrophy of ectopic endometrial implants
• D Weak androgenic steroid that suppresses the mid-cycle LH and FSH surge, producing a hypo-oestrogenic state ✓

Explanation

Danazol is an attenuated 17-alpha ethinyl testosterone derivative. It blunts the mid-cycle surge of LH and FSH without suppressing basal gonadotropins, creating a relatively hypo-oestrogenic environment in which ectopic endometrial tissue atrophies. Its androgenic structure explains the adverse effects of acne, hirsutism, voice deepening and weight gain. Option A describes tamoxifen and option B describes leuprolide, both mechanistically distinct drugs used in related conditions.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.