AdultPediatricDosage Forms & Strengths tablet 20mg 40mg oral suspension 200mg/5mL 625mg/5mL AIDS-Related Cachexia Megace: 800 mg/day PO Megace ES: 312.5-625 mg/day PO Breast Cancer 40 mg PO q6hr Endometrial Cancer 40-320 mg/day PO in divided doses; evaluate efficacy after 2 months of treatment; up to 800 mg/day may be used Cancer-Related Cachexia (Off-label) 480-600 mg/day PO Dosing Modifications Renal impairment: Use with caution; in normal renal function, 57-78% is excreted in urine within 10 daysSafety and efficacy not establishedInteraction CheckerEnter a drug name and megestrolNo Results No Interactions Found Interactions FoundContraindicatedSerious - Use AlternativeSignificant - Monitor CloselyMinorAll Interactions Sort By: SeverityName Contraindicated (0)Serious - Use Alternative (1)mavacamtenmavacamten will decrease the level or effect of megestrol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Progestin and ethinyl estradiol are CYP3A4 substrates. Mavacamten may decrease systemic exposures of ethinyl estradiol and progestin, which may lead to contraceptive failure or an increase in breakthrough bleeding. Advise patients to use a contraceptive method that is not affected by CYP450 enzyme induction (eg, intrauterine system) or add nonhormonal contraception (eg, condoms) during coadministration and for 4 months after last mavacamten dose.Monitor Closely (5)insulin degludecmegestrol decreases effects of insulin degludec by pharmacodynamic antagonism. Use Caution/Monitor. Progestins may impair glucose tolerance.insulin degludec/insulin aspartmegestrol decreases effects of insulin degludec/insulin aspart by pharmacodynamic antagonism. Use Caution/Monitor. Progestins may impair glucose tolerance.insulin inhaledmegestrol decreases effects of insulin inhaled by pharmacodynamic antagonism. Use Caution/Monitor. Progestins may impair glucose tolerance.siponimodsiponimod and megestrol both increase immunosuppressive effects; risk of infection. Use Caution/Monitor. Caution if coadministered because of additive immunosuppressive effects during such therapy and in the weeks following administration. When switching from drugs with prolonged immune effects, consider the half-life and mode of action of these drugs to avoid unintended additive immunosuppressive effects.warfarinmegestrol increases effects of warfarin by unspecified interaction mechanism. Use Caution/Monitor.Minor (2)maitakemaitake increases effects of megestrol by pharmacodynamic synergism. Minor/Significance Unknown. Maitake mushroom has anti-tumor effects (animal/in vitro research).taurinemegestrol decreases levels of taurine by unspecified interaction mechanism. Minor/Significance Unknown.insulin degludecMonitor Closely (1)megestrol decreases effects of insulin degludec by pharmacodynamic antagonism. Use Caution/Monitor. Progestins may impair glucose tolerance.insulin degludec/insulin aspartMonitor Closely (1)megestrol decreases effects of insulin degludec/insulin aspart by pharmacodynamic antagonism. Use Caution/Monitor. Progestins may impair glucose tolerance.insulin inhaledMonitor Closely (1)megestrol decreases effects of insulin inhaled by pharmacodynamic antagonism. Use Caution/Monitor. Progestins may impair glucose tolerance.maitakeMinor (1)maitake increases effects of megestrol by pharmacodynamic synergism. Minor/Significance Unknown. Maitake mushroom has anti-tumor effects (animal/in vitro research).mavacamtenSerious - Use Alternative (1)mavacamten will decrease the level or effect of megestrol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Progestin and ethinyl estradiol are CYP3A4 substrates. Mavacamten may decrease systemic exposures of ethinyl estradiol and progestin, which may lead to contraceptive failure or an increase in breakthrough bleeding. Advise patients to use a contraceptive method that is not affected by CYP450 enzyme induction (eg, intrauterine system) or add nonhormonal contraception (eg, condoms) during coadministration and for 4 months after last mavacamten dose.siponimodMonitor Closely (1)siponimod and megestrol both increase immunosuppressive effects; risk of infection. Use Caution/Monitor. Caution if coadministered because of additive immunosuppressive effects during such therapy and in the weeks following administration. When switching from drugs with prolonged immune effects, consider the half-life and mode of action of these drugs to avoid unintended additive immunosuppressive effects.taurineMinor (1)megestrol decreases levels of taurine by unspecified interaction mechanism. Minor/Significance Unknown.warfarinMonitor Closely (1)megestrol increases effects of warfarin by unspecified interaction mechanism. Use Caution/Monitor. Frequency Not Defined Common Hypertension Insomnia, mood swings Rash, sweating Amenorrhea, breakthrough bleeding, change in menstrual flow, hot sweats, impotence, spotting Diarrhea, flatulence, indigestion, nausea, vomiting, weight gain Serious Deep vein thrombosis (DVT) Pulmonary embolism Thrombophlebitis Anemia Adrenal insufficiency Postmarketing report Asthenia, rash, impotence Overdose may cause shortness of breath, cough, unsteady gait, listlessness, chest pain Contraindications Known or suspected pregnancy Acute thrombophlebitis, thromboembolic disorder, breast cancer Undiagnosed abnormal genital bleeding Prophylaxis of weight loss Documented hypersensitivity May induce vaginal bleeding in women Cautions Diabetes mellitus History of thromboembolic disease Not to be used as prophylaxis against weight loss or as diagnostic test for pregnancy Adrenal insufficiency may occur in patients receiving or being withdrawn from long-term megestrol treatment Megestrol is a progesterone derivative which may induce vaginal bleeding in women Cushing syndrome reported with thearpy Pregnancy Obtain a pregnancy test in females of reproductive potential prior to initiating treatment; advise females of reproductive potential to use effective contraception while taking drug There are no available human data to assess for any drug-associated risks of miscarriage, birth defects, or adverse maternal or fetal outcomes; advise a pregnant women of potential risk to fetus Pregnancy testing is recommended prior to treatment Contraception Therapy may cause fetal harm when administered during pregnancy; advise females of reproductive potential to use effective contraception during treatment Animal data Based on animal data, megestrol acetate may cause fetal harm when administered to a pregnant woman and is contraindicated during pregnancy; there are no adequate animal developmental toxicity data at clinically relevant doses; pregnant rats treated with low doses resulted in reduction in fetal weight and number of live births, and feminization of male fetuses at doses below maximum recommended clinical dosing based on body surface area Lactation The Centers for Disease Control and Prevention recommend that HIV-1 infected mothers not breastfeed their infants to avoid risking postnatal transmission of HIV-1; the drug is present in human milk; there are no data on effects of drug on breastfed infant or on milk production; because of potential for HIV transmission and adverse effects on a breastfed infant, instruct mothers not to breastfeed if they are receiving therapyPregnancy Categories A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk. B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available. Mechanism of Action Progestin derivative with antiestrogenic properties; interferes with estrogen cycle, resulting in lower luteinizing hormone (LH) titer; antineoplastic properties may come from direct effect on endometrium through anti-LH effect mediated via pituitary Absorption Bioavailability: Well absorbed PO Peak plasma time: 1-3 hr (tablet); 3-5 hr (suspension) Metabolism Metabolized by liver Metabolites: Sulfate and glucuronide metabolites (inactive) Elimination Half-life: 13-105 hr (mean, 34 hr) Excretion: Urine (57-78%), feces (8-30%) BRAND FORM. UNIT PRICE PILL IMAGE megestrol oral- 40 mg tabletmegestrol oral- 625 mg/5 mL (125 mg/mL) suspensionmegestrol oral- 400 mg/10 mL (40 mg/mL) suspensionmegestrol oral- 20 mg tabletmegestrol oral- 400 mg/10 mL (40 mg/mL) suspensionmegestrol oral- 400 mg/10 mL (40 mg/mL) suspensionmegestrol oral- 400 mg/10 mL (40 mg/mL) suspensionmegestrol oral- 400 mg/10 mL (10 mL) suspensionmegestrol oral- 400 mg/10 mL (40 mg/mL) suspensionmegestrol oral- 400 mg/10 mL (40 mg/mL) suspensionmegestrol oral- 625 mg/5 mL (125 mg/mL) suspensionmegestrol oral- 40 mg tabletmegestrol oral- 20 mg tabletmegestrol oral- 400 mg/10 mL (10 mL) suspensionmegestrol oral- 400 mg/10 mL (10 mL) suspensionCopyright © 2010 First DataBank, Inc.Print Patient Educationmegestrol oral MEGESTROL - ORAL (me-JES-trol) COMMON BRAND NAME(S): Megace USES: This medication is used to treat cancer of the breast or uterus. Megestrol is similar to a natural substance made by your body called progesterone. HOW TO USE: Take this medication by mouth as directed by your doctor. The dosage and how often you take this medication are based on your medical condition and response to treatment. Follow your doctor's instructions carefully.Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time(s) each day.Do not increase your dose or use this drug more often or for longer than prescribed. Your condition will not improve any faster, and your risk of side effects will increase.Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets. SIDE EFFECTS: Trouble sleeping, fever, gas, decreased sexual ability/desire, weight gain, changes in appetite, or upset stomach may occur. Women may have changes in their menstrual periods, including unpredictable bleeding. If any of these effects last or get worse, tell your doctor or pharmacist promptly.Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.Tell your doctor right away if you have any serious side effects, including: fast/pounding heartbeat, fatigue, headache, swelling of the hands/feet.This medication may rarely make your blood sugar rise, which can cause or worsen diabetes. Tell your doctor right away if you have symptoms of high blood sugar such as increased thirst/urination. If you already have diabetes, check your blood sugar regularly as directed and share the results with your doctor. Your doctor may need to adjust your diabetes medication, exercise program, or diet.Get medical help right away if you have any very serious side effects, including: symptoms of a blood clot (such as chest pain, trouble breathing, pain/redness/swelling of arms or legs), confusion, mental/mood changes, weakness/numbness on one side of the body, trouble speaking, vision changes.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345. PRECAUTIONS: Before taking megestrol, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: adrenal gland problems (such as Cushing's syndrome), blood clots, diabetes, heart disease (such as congestive heart failure), high blood pressure, kidney disease, stomach or abdominal problems, unusual vaginal bleeding.If you have diabetes, this product may affect your blood sugar. Check your blood sugar regularly as directed and share the results with your doctor. Tell your doctor right away if you have symptoms of high blood sugar (see Side Effects section). Your doctor may need to adjust your diabetes medication, exercise program, or diet.Using megestrol for a long time may make it more difficult for your body to respond to physical stress. Before having surgery or emergency treatment, or if you get a serious illness/injury, tell your doctor or dentist that you are using this medication or have recently stopped taking it. Tell your doctor right away if you develop unusual/extreme tiredness, dizziness, nausea, or vomiting.Older adults may be more sensitive to the side effects of this drug, especially the risk for blood clots.Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using megestrol. Megestrol may harm an unborn baby. Your doctor should order a pregnancy test before starting this medication. Ask about reliable forms of birth control while using this medication. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.Since this drug can be absorbed through the skin and lungs and may harm an unborn baby, women who are pregnant or who may become pregnant should not handle this medication or breathe the dust from the tablets.This medication passes into breast milk. Consult your doctor before breast-feeding. DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products)