MGA is used mainly as an appetite stimulant to promote weight gain in a variety of situations. When given at very high dosages, it can substantially increase appetite in most individuals, even those with advanced cancer, and is often used to boost appetite and induce weight gain in patients with cancer or HIV/AIDS-associated cachexia. In addition to its effects on appetite, MGA appears to have antiemetic effects. MGA is also used as an antineoplastic agent in the treatment of breast cancer and endometrial cancer. It is significantly inferior to aromatase inhibitors in both clinical effectiveness and tolerability as a second-line therapy for breast cancer after tamoxifen failure. MGA was formerly used in combined oral contraceptives in combination with ethinylestradiol or mestranol, and has been used in a combined injectable contraceptive in combination with estradiol as well. Although it has not been approved for these uses, MGA has been studied and/or used off-label for a variety of indications including menopausal hormone therapy and the treatment of hot flashes, gynecological/menstrual disorders, endometriosis, endometrial hyperplasia, ovarian cancer, prostate cancer, benign prostatic hyperplasia, male breast cancer, and precocious puberty. MGA can also be used to treat pattern hair loss in men, but its side effects generally make it unacceptable for this purpose. Appetite stimulation is achieved with MGA with oral dosages of 400 to 800 mg/day. The optimal dosage with maximum effect for appetite stimulation has been determined to be 800 mg/day. The recommended oral dosage of MGA for breast cancer is 40 mg four times per day (160 mg/day total), while the medication is used at an oral dosage of 40 to 320 mg/day in divided doses for endometrial cancer. It has been used at far lower dosages (e.g., 1–5 mg/day oral, 25 mg/month ) in combination with an estrogen for contraceptive purposes. Available forms MGA is available as 5 mg, 20 mg, and 40 mg oral tablets and in oral suspensions of 40 mg/mL, 125 mg/mL, 625 mg/5 mL, and 820 mg/20 mL. It was used at doses of 1 mg, 2 mg, 4 mg, and 5 mg in combined oral contraceptives. MGA is formulated at a dose of 25 mg in combination with a dose of 3.75 mg estradiol in a microcrystalline aqueous suspension for use as a once-monthly combined injectable contraceptive in women.
Megestrol acetate
Hexestrol
Gestodene
Fosfestrol
Moxestrol
Dienestrol
Pentagestrone acetate
Dimestrol