Clomiphene (Clomifene)
- Atc Codes:G03GB02
- CAS Codes:50-41-9#911-45-5
- PHARMGKB ID:50-41-9#911-45-5
Table of contents
- Brand Names
- Chemistry
- Pharmacologic Category
- Mechanism of Action
- Therapeutic Use
- Pregnancy and Lactation Implications
- Contraindications
- Warnings and Precautions
- Adverse Reactions
- Genes that may be involved
- Substrate of
- Dosage
- Pharmacokinetics and Pharmacodynamics
- Special Considerations
Brand Names
Europe
Austria: Clomiphen; Belgium: Clomid, Pergotime; Bulgaria: Clostilbegyt; Cyprus: Clomid, Duinum, Ova-Mit; Czech Republic: Clostilbegyt; Denmark: Pergotime; Finland: Clomifen; France: Clomid, Pergotime; Germany: Clomhexal, Clomifen, Pergotime; Greece: Clomiphen, Serpafar; Hungary: Clostilbegyt; Ireland: Clomid; Italy: Clomid, Serophene; Latvia: Clostilbegyt; Lithuania: Clostilbegyt; Luxembourg: Clomid, Pergotime; Malta: Clomid, Ova-Mit; Netherlands: Clomid, Serophene; Poland: Clostilbegyt; Portugal: Dufine; Romania: Clostilbegyt, Ova-Mit; Slovakia: Clostilbegyt; Slovenia: Klomifen; Spain: Onmifin; Sweden: Pergotime; UK: Clomid, Clomifene.
North America
Canada: Clomid, Serophene; USA: Clomid, Milophene, Serophene.
Latin America
Argentina: Genozym, Serophene, Tocofeno; Brazil: Clomid, Indux, Serophene; Mexico: Omifin.
Asia
Japan: Clomid, Clomiphene, Orifen, Phemilon, Serophene, Spacromin.
Drug combinations
Chemistry
Clomiphene Citrate: C~26~H~28~ClNO C~6~H~8~O~7~. Mw: 598.08. (1) Ethanamine, 2-[4-(2-chloro-1,2-diphenylethenyl)phenoxy]-N,N-diethyl-, 2-hydroxy-1,2,3-propanetricarboxylate (1:1); (2) 2-[p-(2-Chloro-1,2-diphenylvinyl)phenoxy]triethylamine citrate (1:1). CAS-50-41-9; CAS-911-45-5 (clomiphene)(1964).
Pharmacologic Category
Estrogen Agonist-Antagonists. Ovulation Stimulator. Selective Estrogen Receptor Modulator. (ATC-Code: G03GB02).
Mechanism of action
Clomiphene is a racemic mixture consisting of zuclomiphene and enclomiphene, each with distinct pharmacologic properties. Enclomiphene is much less potent in inducing ovulation, but it is more rapidly absorbed and metabolized, allowing the more potent activity of zuclomiphene to predominate. Zuclomiphene acts at the hypothalamus, occupying cell surface and intracellular estrogen receptors for longer durations than estrogen. This interferes with receptor recycling, effectively depleting hypothalamic estrogen receptors and inhibiting normal estrogenic negative feedback. Impairment of the feedback signal results in increased pulsatile GnRH secretion from the hypothalamus and subsequent pituitary gonadotropin (FSH, LH) release, causing growth of the ovarian follicle, followed by follicular rupture.
Therapeutic use
Ovulatory failure in patients desiring pregnancy.
Pregnancy and lactiation implications
Embryotoxic effects observed in animals. Multiple births occur in 10% of pregnancies with induced ovulation. Increased frequency of delayed follicular rupture and ectopic pregnancy also noted. Not indicated for use in women who are already pregnant. Excretion in breast milk unknown (may decrease lactation).
Unlabeled use
Contraindications
Hypersensitivity to clomiphene or any of its components. Liver disease. Abnormal uterine bleeding. Enlargement or development of ovarian cyst (not due to polycystic ovarian syndrome). Uncontrolled thyroid or adrenal dysfunction. Organic intracranial lesion such as pituitary tumor. Pregnancy.
Warnings and precautions
Ovarian enlargement may be accompanied by abdominal distention or abdominal pain. Ovarian hyperstimulation syndrome is characterized by severe ovarian enlargement, abdominal pain/distention, nausea, vomiting, diarrhea, dyspnea, and oliguria, and may be accompanied by ascites, pleural effusion, hypovolemia, electrolyte imbalance, hemoperitoneum, and thromboembolic events. Visual disturbances can occur. Use with caution in patients unusually sensitive to pituitary gonadotropins (e.g. polycystic ovarian syndrome). Multiple births may result from the use of these medications. Clomiphene may increase levels of serum thyroxine and thyroxine-binding globulin.