Delmadinone is a steroid with progestogenic, anti-androgenic and weak glucocorticoid action, synthesized in Syntex S.A. Acetate ester of delmadinone is used in veterinary under tradenames Tardak for cats and dogs for the treatment of excessive or aberrant sexual behaviour, including vagrancy, for the relief of prostatic hypertrophy, circum-anal tumors and for the treatment of certain forms of aggressiveness, nervousness, epileptiform seizures and corticosteroid-resistant pruritus. Delmadinone acetate blocks androgen receptors inhibit 5-reductase, which catalyzes the transformation of testosterone to the more potent androgen 5-dihydrotestosterone and decreases the production of testosterone by inhibiting gonadotropin release.