Gestrinone

Gestrinone is a synthetic steroid with mixed progestogen and antiprogestogen (i.e., partial agonist) effects, and also has some mild androgenic activity. It is marketed under the names Dimetriose, Dimetrose, and Nemestran, as a treatment for endometriosis. Gestrinone is available in many countries, but not in the USA. As it has anabolic effects, its use in competition has been banned by the International Olympic Committee.

Gestrinone is a 19-nortestosterone derivative.

Method of action

Its mechanism of action consists of suppression of the release of pituitary gonadotropins. Gestrinone also interacts with the endometrium, inhibiting its growth. The inhibition is the result of gestrinone's interaction with the androgen receptor; this is also the reason for androgenic side effects. Gestrinone has been shown to interact with the estrogen receptor, the androgen receptor, and the progesterone receptor.

Metabolism

The drug is well absorbed via the oral route, passed through the liver, and has a half-life of about 24 hours. It is metabolized by the liver and excreted by urine and feces.