Article: Danazol

Danazol
Systematic (IUPAC) name
?, alternative: 17beta-hydroxy-2,4,17alpha-pregnadien-20-yno[2,3-D]isoxazole
Identifiers
CAS number	17230-88-5
ATC code	G03XA01
PubChem	28417
Chemical data
Formula	C22H27NO2
Mol. weight	337.5
Pharmacokinetic data
Bioavailability	?
Metabolism	liver
Half life	?
Excretion	?
Therapeutic considerations
Pregnancy cat.	X (USA)
Legal status	Rx (USA)
Routes	oral

Danazol is a derivative of the synthetic steroid ethisterone, a modified testosterone. It was approved by the Food and Drug Administration (FDA) as the first drug to treat specifically endometriosis, but its role as a treatment for endometriosis has been largely replaced by the GnRH agonists.

The agent is fat-soluble, has a molecular weight of 337.5. Its CAS registry number is 17230-88-5.

Danazol decreases the pituitary hormones FSH and LH and exerts an antiproliferative effect upon the endometrium, leading to amenorrhea. This effect is useful for patients with endometriosis. Commonly, pelvic pain associated with endometriosis is improved as well.

Androgenic side effects are of concern as in sensitive female individuals, Danazol can enhance unwanted hair growth leading to hirsutism. On rare occasion, it may deepen the voice. Other side effects could be acne and oily skin. As Danazol is metabolized by the liver, it cannot be used by patients with liver disease, and long-term use needs to monitor liver function on a periodic basis. Some patients who use Danazol may experience weight gain and fluid retention.

Contrary to GNRH agonists Danazol does not induce osteoporosis. Also, symptoms of hot flashes tend to be less common or severe.

Danazol is contraindicated in pregnancy as it could masculinize a female fetus.

Danazol has been used for other indications, namely in the management of menorrhagia, of fibrocystic breast disease, and of hereditary angioedema.

In the USA, Danazol was initially marketed as Danocrine, before it became available as a generic drug.