Comparative Pharmacology
Head-to-head clinical analysis: AMEN versus MEGACE ES.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AMEN versus MEGACE ES.
AMEN vs MEGACE ES
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Progesterone receptor agonist; induces secretory endometrium, inhibits gonadotropin release, and alters cervical mucus.
Megestrol acetate is a synthetic progestin that inhibits pituitary gonadotropin secretion, leading to suppression of ovarian and testicular hormone production. It also has antineoplastic effects possibly through local action on hormone-sensitive tissues and stimulates appetite via modulation of neuropeptide Y and other appetite-regulating factors.
Medroxyprogesterone acetate (AMEN): 5-10 mg orally once daily for 5-10 days, starting on day 16 or 21 of menstrual cycle; also 150 mg IM every 3 months for contraception.
625 mg orally once daily (MEGACE ES suspension contains 625 mg/5 mL; shake well before use). For appetite stimulation in cachexia.
None Documented
None Documented
Terminal elimination half-life is approximately 4-6 hours. In severe hepatic impairment, half-life may be prolonged up to 12 hours.
Approximately 34 hours in plasma; steady-state achieved after 2-3 weeks of daily dosing.
Primarily hepatic metabolism to inactive metabolites, with <1% excreted unchanged in urine. Fecal elimination of metabolites accounts for ~30%.
Primarily renal (≤1% unchanged) and biliary; extensive metabolism to inactive glucuronide conjugates excreted in feces.
Category C
Category C
Progestin
Progestin