This is an anti-estrogens.

They induce gonadotropin release by occupying oestrogen receptors in the hypothalamus, thereby interfering with feedback mechanisms; chorionic gonadotropin is sometimes used as an adjunct. Patients should be informed that there is a risk of multiple pregnancy (rarely more than twins).

Indications: female infertility due to oligomenorrhoea or secondary amenorrhoea (e.g. associated with polycystic ovarian disease); anovulatory infertility; oligospermia.

Cautions: In polycystic ovary syndrome to be used with caution as cysts may enlarge during treatment, ovarian hyperstimulation syndrome may occur, uterine fibroids, ectopic pregnancy, incidence of multiple births increased, visual symptoms (discontinue and consult ophthalmologist); breast-feeding, clomifene should not normally be used for longer than 6 cycles (increased risk of ovarian cancer).

Contra-indications: ovarian cysts, hepatic disease, hormone dependent tumours or undiagnosed abnormal uterine bleeding, pregnancy (to be excluded before initiating treatment).

Side Effects: visual blurring (withdraw), ovarian hyperstimulation (withdraw), hot flushes, abdominal discomfort, occasionally nausea, vomiting, depression, insomnia, breast tenderness, headache, intermenstrual spotting, menorrhagia, endometriosis, convulsions, weight gain, rashes, dizziness, hair loss.

Dose: 50 mg daily for 5 days, starting within about 5 days of onset of menstruation (preferably on 2nd day) or at any time (normally preceded by a progestogen-induced withdrawal bleed) if cycles have ceased; second course of 100 mg daily for 5 days may be given in absence of ovulation; most patients who are going to respond will do so to first course; 3 courses should constitute adequate therapeutic trial; long-term cyclical therapy not recommended.