Megestrol belongs to a group of medications known as progestogens. Megestrol is used to treat Prostate Cancer because testosterone is needed by prostate cancer cells for growth. It prevents the release of a hormone required for production of testosterone in the testicles.

Megestrol also slows the growth of breast and endometrium (lining of the uterus) cancer cells by interfering with other hormones and proteins that are required for growth of the cancer cells. It is also used to treat appetite loss and severe weight or muscle loss in people with cancer or acquired immunodeficiency syndrome (AIDS). It helps these conditions by promoting the production of certain proteins that increase appetite and weight gain.

Megestrol may be available under multiple brand names and/or in several different forms. Any specific brand name of Megestrol may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of Megestrol may not be used for all of the conditions discussed here.

Your doctor may have suggested Megestrol for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking Megestrol, speak to your doctor. Do not stop taking Megestrol without consulting your doctor.

Do not give Megestrol to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take Megestrol if their doctor has not prescribed it.

The recommended dose depends on the condition being treated and body weight.

For people with prostate cancer, the recommended dose is 120 mg taken as a single daily dose in combination with diethylstilbestrol 0.1 mg.

For people with Breast Cancer, the usual dose is 160 mg daily. This dose may be divided into 4 equal doses of 40 mg.

For people with cancer of the endometrium, the usual dose is 80 mg to 320 mg daily, which can be divided into 40 mg tablets taken 2 to 4 times daily, or 160 mg tablets taken 1 to 2 times daily.

For people with cancer or AIDS and appetite loss, muscle wasting, or significant weight loss, the usual adult dose is 400 mg to 800 mg as a single daily dose. People with AIDS usually use the liquid form of Megestrol. Shake the liquid well before measuring the dose.

The effectiveness of megestrol acetate can be assessed after 2 months have passed following the start of therapy.

Many things can affect the dose of a medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

Megestrol can be taken with or without food.

Use an oral syringe to measure each dose of the liquid, as it gives a more accurate measurement than household teaspoons.

It is important to take Megestrol exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

The tablets and liquid should be stored at room temperature in a cool, dry place.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes Megestrol. If you are concerned about side effects, discuss the risks and benefits of Megestrol with your doctor.

The following side effects have been reported by at least 1% of people taking Megestrol. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

• Constipation
• Diarrhea
• hair loss
• increased appetite
• mild blood pressure increase
• mood changes
• nausea or vomiting
• swelling of the face, ankles, or feet
• weight gain

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• breast enlargement
• changes in vaginal bleeding
• decreased hearing
• decreased interest or ability in sexual activity
• Depression
• filling or rounding out of face
• hot flushes
• impotence
• increased flow of breast milk
• increased urination
• loss of appetite
• mood changes
• rash
• shortness of breath
• symptoms of high blood sugar (e.g., frequent urination, increased thirst, excessive eating, unexplained weight loss, poor wound healing, infections, fruity breath odour)
• unusual tiredness or weakness

Stop taking the medication and seek immediate medical attention if any of the following occur:

• signs of Stroke (e.g., sudden or severe headache; sudden loss of coordination; vision changes; sudden slurring of speech; or unexplained weakness, numbness, or pain in arm or leg)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking Megestrol.

40 mg
Each light blue, round, flat-faced, bevelled-edged, scored tablet, engraved "40" on one side, contains megestrol acetate 40 mg. Nonmedicinal ingredients: colloidal silicon dioxide, croscarmellose sodium, lactose, magnesium stearate, microcrystalline cellulose, and Brilliant Blue FCF Lake 12% (dye).

160 mg
Each white, oval, biconvex, scored tablet engraved "160" on one side, contains megestrol acetate 160 mg. Nonmedicinal ingredients: colloidal silicon dioxide, croscarmellose sodium, lactose, magnesium stearate, and microcrystalline cellulose.

Do not take megestrol if you:

• are allergic to megestrol acetate or any ingredients of the medication
• are or may be pregnant (first 4 months)

There may be an interaction between megestrol acetate and any of the following:

• Apixaban
• Cyclosporine
• dabigatran
• diabetes medications (e.g., chlorpropamide, glipizide, Glyburide, insulin, Metformin, Nateglinide, Rosiglitazone)
• dofetilide
• Heparin and low-molecular weight heparins (e.g., Dalteparin, Tinzaparin)
• Rivaroxaban
• testosterone and androgens(for men taking megestrol to treat prostate cancer)
• estrogen (for women taking megestrol for breast or endometrial cancer)
• Ulipristal
• Warfarin

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

• stop taking one of the medications,
• change one of the medications to another,
• change how you are taking one or both of the medications, or
• leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with Megestrol. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the Nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.