About mesterolonea synthetic, orally effective dihydrotestosterone derivative, androgen.mechanism of action of mesterolonemesterolone is an orally active synthetic testosterone derivative. testosterone and it`s reduced form- dihydrotestosterone binds with cytoplasmic testosterone receptors in androgen responsive organs and tissues and forms hormone receptor complex. this hormone-receptor complex binds with dna and enhances dna transcription and formation of mrna which ultimately leads to modification of protein synthesis. it promotes growth and development of male sex organs and secondary sexual characters and maintains proper sexual functioning. it also exerts anabolic effect on skeleton and skeletal muscles and accelerates erythropoiesis. it causes less feed back inhibition of gonadotropin secretion and spermatogenesis than testosterone. also it does not cause hepatic impairment.