Clomid or clomiphene is an antiestrogenic preparation of non-steroidal structure. The mechanism of action is determined by the ability to specifically bind to estrogen receptors in the hypothalamus and ovaries. In small doses the preparation increases the secretion of gonadotropins (prolactin, follicle-stimulating and luteinizing hormone) and stimulates ovulation. In hypoestrogenemia it shows moderate estrogenic action, and in hyperestrogenemia it acts as an antiestrogen. In high doses it inhibits the secretion of gonadotrophins. It has no gestagen or androgen effect.