Comparative Pharmacology
Head-to-head clinical analysis: LEVONORGESTREL versus MEGACE ES.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LEVONORGESTREL versus MEGACE ES.
LEVONORGESTREL vs MEGACE ES
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Synthetic progestin that suppresses gonadotropin release (GnRH, LH, FSH) via negative feedback on the hypothalamic-pituitary-ovarian axis; inhibits ovulation, thickens cervical mucus, and alters endometrial lining.
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.
For emergency contraception: 1.5 mg orally as a single dose or 0.75 mg orally 12 hours apart. For hormonal contraception: 0.03 mg to 0.05 mg orally once daily in combined oral contraceptives; for progestin-only oral contraceptive (mini-pill): 0.03 mg orally once daily. For intrauterine system (IUD): 52 mg intrauterine device inserted for up to 5 years.
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
Clinical Note
moderateLevonorgestrel + Sulfisoxazole
"The metabolism of Sulfisoxazole can be decreased when combined with Levonorgestrel."
Clinical Note
moderateLevonorgestrel + Erythromycin
"The metabolism of Erythromycin can be decreased when combined with Levonorgestrel."
Clinical Note
moderateLevonorgestrel + Cyclosporine
"The metabolism of Cyclosporine can be decreased when combined with Levonorgestrel."
Clinical Note
moderateLevonorgestrel + Fluconazole
Terminal half-life: 24-30 hours (range 11-45 hours). This prolonged half-life supports once-daily or extended-cycle dosing in contraceptive formulations.
Approximately 34 hours in plasma; steady-state achieved after 2-3 weeks of daily dosing.
Renal: 45-60% (metabolites), Fecal: 32-45% (unchanged and metabolites). Biliary excretion contributes to fecal elimination.
Primarily renal (≤1% unchanged) and biliary; extensive metabolism to inactive glucuronide conjugates excreted in feces.
Category C
Category C
Progestin
Progestin
"The metabolism of Fluconazole can be decreased when combined with Levonorgestrel."