Generic
Megestrol Acetate
27 brands available in the market
At a glance
Megestrol Acetate is a progestin used for the palliative treatment of breast cancer and endometrial cancer, and for anorexia, cachexia, and unexplained significant weight loss in AIDS and cancer patients.
Description
Megestrol Acetate is a synthetic antineoplastic and progestational drug. Its antineoplastic mechanism may involve inhibition of pituitary gonadotropin production and decreased estrogen secretion, modification of other steroid hormone actions, and direct cytotoxic effects on tumor cells.
Indications
- Advanced breast carcinoma (palliative treatment)
- Advanced endometrial carcinoma (palliative treatment)
- Anorexia, cachexia, and unexplained significant weight loss in AIDS and cancer patients
Therapeutic class
Progestin Antineoplastic
Pharmacological class
Synthetic Progestogen
Pharmacology
Megestrol Acetate inhibits pituitary gonadotropin production, decreases estrogen secretion, modifies other steroid hormone actions, and exerts direct cytotoxic effects on tumor cells.
Mechanism of action
Increases appetite to promote weight gain and inhibits growth of hormone-dependent cancers.
Dosage
Breast Carcinoma: 160 mg/day
Endometrial Carcinoma: 40-320 mg/day in divided doses
Anorexia/Cachexia (AIDS/Cancer): 800 mg/day initial; usual range 400-800 mg/day
Administration
- Swallow tablet whole; do not chew, crush or break
- May be taken with or without food, but at a fixed time is preferable
- At least 2 months of treatment needed to see appetite changes
Missed dose
If you miss a dose, take it as soon as you remember; skip if it's almost time for next dose; do not double the dose.
Side effects
Common Side Effects:
- Weight gain (most common)
- Nausea, vomiting
- Edema
- Breakthrough uterine bleeding (1-2%)
- Hot flashes
- Hypertension
- Hyperglycemia
Precautions & warnings
- Caution in patients with history of thrombophlebitis
- Caution in patients with severe impaired liver function
- May have adrenocortical effects
- Do not use in patients with galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption
- Contraindicated in pregnancy and lactation
Contraindications
- Pregnancy (known or suspected)
- Hypersensitivity to the drug
- Severe hepatic impairment
Drug interactions
- Indinavir concentrations may be reduced
- Possible reduced efficacy of cisplatin
- Warfarin half-life may be increased
- Megestrol concentration may be decreased by aminoglutethimide and enzyme-inducing drugs
Food interactions
Safety with alcohol is not known; consult your doctor.
Use in pregnancy
Use in Pregnancy: Megestrol Acetate is highly unsafe during pregnancy; exposure in the first 4 months may increase risk of fetal genital abnormalities.
Pregnancy Category: X — always consult a doctor before taking during pregnancy.
Use in lactation
Use in Lactation: Megestrol Acetate is probably unsafe during breastfeeding; do not use.
Pediatric use
Safety and effectiveness not established in pediatric patients.
Geriatric use
Caution needed in elderly (higher risk of decreased renal function); dose adjustment may be needed.
Renal / hepatic impairment
Renal Impairment: Caution in severe kidney disease; dose adjustment may be needed (drug is substantially excreted by the kidney).
Hepatic Impairment: Caution in severe liver disease; dose adjustment may be needed.
Overdose effects
Overdose may cause diarrhea, nausea, abdominal pain, shortness of breath, cough, unsteady gait, listlessness, and chest pain; no specific antidote; supportive treatment.
Storage conditions
Store below 30°C in a cool and dry place, away from light and moisture; keep out of reach of children.
Chemical structure
Megestrol Acetate