Pronunciation: me-JES-trole AS-eh-tate
- Suspension 40 mg/mL
- Suspension 125 mg/mL
- Tablets 20 mg
- Tablets 40 mg
Megace OS (Canada)
Inhibits secretion of pituitary gonadotropins with a resultant decrease in estrogen secretion; exerts a direct cytotoxic effect on tumor cells; mechanism of effect on anorexia and cachexia is unknown.
C max is 10 to 56 ng/mL; T max is 1 to 3 h for tablets. C max is approximately 753 ng/mL, and T max is approximately 5 h for suspension.
The megestrol acetate metabolites are negligible.
The major route for elimination is urine; minor routes are feces and respiratory, as CO 2 . The t ½ is 13 to 104.9 h (mean, 34.2 h) for tablets.
Indications and UsageOral suspension
Treatment of anorexia, cachexia, or an unexplained weight loss in patients diagnosed with AIDS.Tablets
Palliative treatment of advanced inoperable, recurrent, or metastatic carcinoma of breast or endometrium.
Hypersensitivity to progestins or any component of these formulations; known or suspected pregnancy (suspension).
Dosage and AdministrationBreast Cancer
PO 40 mg 4 times daily.Endometrial Cancer
PO 40 to 320 mg/day in divided doses.Anorexia, Cachexia, Unexplained Weight Loss in AIDS patients
PO 800 mg/day. PO 625 mg/day ( Megace ES ).
- Shake suspension well before using.
Store tablet in dry, cool place at room temperature (59° to 86°F).
Store suspension between 59° and 77°F. Dispense in tight container. Protect from light.
Elevated dofetilide plasma concentrations may occur. Do not use concurrently.Indinavir
Coadministration results in a significant decrease in C max and AUC of indinavir.
Laboratory Test Interactions
None well documented.
Hypertension (8%); cardiomyopathy, palpitation (1% to 3%); heart failure, thromboembolic phenomena, including pulmonary embolism and thrombophlebitis.
Headache (10%); asthenia (6%); abnormal thinking, confusion, convulsion, depression, hyperesthesia, neuropathy, paresthesia (1% to 3%); hot flashes, lethargy, malaise, mood changes.
Rash (2%); alopecia, pruritus, skin disorder, sweating, vesiculobullous rash (2%).
Amblyopia, pharyngitis (2%).
Diarrhea (15%); flatulence (10%); vomiting (6%); nausea (5%); dyspepsia (4%); abdominal pain or discomfort, constipation, dry mouth, increased salivation, oral moniliasis (1% to 3%).
Impotence (14%); decreased libido (5%); urinary frequency (2%); albuminemia, breakthrough bleeding, gynecomastia, urinary incontinence, UTI (1% to 3%).
Leukopenia (1% to 3%).
Anemia (5%); hepatomegaly (1% to 3%).
Hyperglycemia (6%); increased LDH, peripheral edema (1% to 3%); glucose intolerance.
Pneumonia (2%); cough, dyspnea, lung disorder (1% to 3%).
Fever, pain (6%); chest pain, edema, herpes, infection, moniliasis, sarcoma (1% to 3%); carpal tunnel syndrome, increased appetite, tumor flare, weight gain.
Category D .Suspension
Category X .
Excreted in breast milk.
Safety and efficacy not established.
Use with caution, usually starting at the low end of the dosage range because of the greater frequency of decreased cardiac, hepatic, or renal function, and concomitant diseases or other drug therapy.
Adrenal insufficiency may occur in patients receiving or being withdrawn from chronic megestrol acetate therapy.
New onset diabetes mellitus and exacerbation of preexisting diabetes mellitus has occurred.
Use with caution in patients with history of thromboembolic disease.
- Explain potential significance of breakthrough bleeding, irregular menstrual cycles, and possible lack of menstrual cycle. Tell patient to notify health care provider of heavy or continuous menstrual flow.
- Encourage patients with diabetes to monitor blood glucose more frequently until effect on diabetes control has been determined.
- Instruct patient to report these symptoms to health care provider: chest pain; clay-colored stools; dark urine; dyspnea; edema; jaundice; numbness in extremities; pain in calves of legs with redness, warmth, and swelling; sudden severe headache; visual disturbances.
- Inform patient about the product differences in dosages. Depending on the indications for use, the various oral suspensions contain different amounts of megestrol acetate in 5 mL.
- Instruct patient to report any adverse reactions.
- Advise women of childbearing potential to use contraception and avoid becoming pregnant while taking this drug.
Copyright © 2009 Wolters Kluwer Health.