Danazol is a synthetic derivative of ethisterone which is approved by FDA for the treatment of endometriosis, fibrocystic breast disease and for preventing hereditary angioedema. It is believed that the in vivo therapeutic effect is achieved through activating androgen receptors. Danazol has teratogenic effects.

Ethisterone is a metabolite of danazol. Ethisterone is a progestogen hormone. The first orally active progestin, Ethisterone (brand names Pranone, Progestoral, Lutocylol, Proluton C), also known as 17α-ethinyltestosterone, pregneninolone, or anhydrohydroxyprogesterone, is a steroidal progestin with androgenic activity which is derived from testosterone and was introduced for medical use in 1939. Ethisterone is indicated for progesterone supplementation or replacement as part of an Assisted Reproductive Technology (ART) treatment for infertile women with progesterone deficiency and for the treatment of secondary amenorrhea. Also used as a female contraceptive.