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What is Which of the following is not an anti-androgenic drug? and explain in detail?
Reference: Katzung, Basic & Clinical Pharmacology, 13th ed., Pgs. 737 & 738.
 
Since dihydrotestosterone—not testosterone—appears to be the essential androgen in the prostate, androgen effects in this and similar dihydrotestosterone-dependent tissues can be reduced by an inhibitor of 5α-reductase. Finasteride, a steroidlike inhibitor of this enzyme, is orally active and causes a reduction in dihydrotestosterone levels.
Cyproterone and cyproterone acetate are effective antiandrogens that inhibit the action of androgens at the target organ. The acetate form has a marked progestational effect that suppresses the feedback enhancement of LH and FSH, leading to a more effective antiandrogen effect.
Flutamide, a substituted anilide, is a potent antiandrogen that has been used in the treatment of prostatic carcinoma. Although not a steroid, it behaves like a competitive antagonist at the androgen receptor.