Danazol (Danocrine) and gestrinone (Dimetrose, Nemestran) are suppressive steroids with some androgenic activity. Both agents inhibit the growth of endometriosis but their use has declined, due in part to virilizing side effects such as excessive hair growth and voice changes. There is tentative evidence based on cohort studies that dienogest and norethisterone acetate (NETA) may help patients with DIE in terms of pain. There is tentative evidence based on a prospective study that vaginal danazol reduces pain in those affected by DIE. Gonadotropin-releasing hormone (GnRH) modulators: These drugs include GnRH agonists such as leuprorelin (Lupron) and GnRH antagonists such as elagolix (Orilissa) and are thought to work by decreasing estrogen levels. A 2010 Cochrane review found that GnRH modulators were more effective for pain relief in endometriosis than no treatment or placebo, but were not more effective than danazol or intrauterine progestogen, and had more side effects than danazol. A 2018 Swedish systematic review found that GnRH modulators had similar pain-relieving effects to gestagen, but also decreased bone density. Aromatase inhibitors are medications that block the formation of estrogen and have become of interest for researchers who are treating endometriosis. Examples of aromatase inhibitors include anastrozole and letrozole. Evidence for aromatase inhibitors is confirmed by numerous controlled studies that show benefit in terms of pain control and quality of life when used in combination with gestagens or oral contraceptives with less side-effects when used in combination with oral contraceptives like norethisterone acetate.
Endometriosis is a disease of the female reproductive system in which cells similar to those in the endometrium, the layer of tissue that normally covers the inside of the uterus, grow outside the uterus. Most often this is on the ovaries, fallopian tubes, and tissue around the uterus and ovaries; in rare cases it may also occur in other parts of the body. Some symptoms include pelvic pain, heavy periods, pain with bowel movements, and infertility. Nearly half of those affected have chronic pelvic pain, while in 70% pain occurs during menstruation. Pain during sexual intercourse is also common. Infertility occurs in up to half of affected individuals. About 25% of individuals have no symptoms and 85% of those seen with infertility in a tertiary center have no pain. Endometriosis can have both social and psychological effects.The cause is not entirely clear. Risk factors include having a family history of the condition. The areas of endometriosis bleed each month (menstrual period), resulting in inflammation and scarring. The growths due to endometriosis are not cancer. Diagnosis is usually based on symptoms in combination with medical imaging; however, biopsy is the surest method of diagnosis. Other causes of similar symptoms include pelvic inflammatory disease, irritable bowel syndrome, interstitial cystitis, and fibromyalgia. Endometriosis is commonly misdiagnosed and people often report being incorrectly told their symptoms are trivial or normal.