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 Megace OS (Megestrol). If you are concerned about side effects, discuss the risks and benefits of Megace OS (Megestrol) with your doctor.

The following side effects have been reported by at least 1% of people taking Megace OS (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 Megace OS (Megestrol).

Each mL of lemon-lime flavoured oral suspension contains Megace OS (Megestrol) acetate 40 mg. Nonmedicinal ingredients: anhydrous citric acid, natural and artificial lemon-lime flavour, polyethylene glycol 1450, polysorbate 80, purified water, sodium benzoate, sodium citrate dihydrate, sucrose, and xantham gum.

Do not take Megace OS (Megestrol) if you:

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

There may be an interaction between Megace OS (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 Megace OS (Megestrol) to treat prostate cancer)
• estrogen (for women taking Megace OS (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 Megace OS (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.

Before you begin taking a medication, be sure to inform your doctor of any medical conditions or Allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should take Megace OS (Megestrol).

Blood Clots: Megace OS (Megestrol) may increase the chance of blood clot formation, which will cause blood flow to organs or to the extremities to be reduced.

If you have a history of clotting, you may be at increased risk of experiencing blood clot-related problems such as Heart Attack, stroke, or clots in the deep veins of your leg. Discuss with your doctor how Megace OS (Megestrol) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Megace OS (Megestrol), and whether any special monitoring is needed.

If you experience symptoms such as sharp pain and swelling in the leg, difficulty breathing, chest pain, blurred vision or difficulty speaking, contact your doctor immediately.

Diabetes: Megace OS (Megestrol) acetate may cause a loss of control of diabetes by increasing blood sugar levels and changing glucose tolerance. If you have diabetes, you may find it necessary to monitor your blood sugar more frequently while using Megace OS (Megestrol).

If you have diabetes or are at risk for developing diabetes, discuss with your doctor how Megace OS (Megestrol) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Megace OS (Megestrol), and whether any special monitoring is needed. You may need to check your blood glucose levels more often.

Kidney Disease: Kidney disease or reduced kidney function may cause Megace OS (Megestrol) to build up in the body, causing side effects. If you have kidney problems, discuss with your doctor how Megace OS (Megestrol) may affect your medical condition, how your medical condition may affect the dosing and effectiveness of Megace OS (Megestrol), and whether any special monitoring is needed. Your doctor may want to test your liver function regularly with blood tests while you are taking Megace OS (Megestrol).

Osteoporosis: Long-term use of Megace OS (Megestrol) can increase the risk of osteoporosis (brittle bones). Talk to your doctor about ways to help prevent osteoporosis. Your doctor will monitor your bone density if you take Megace OS (Megestrol) for a long period of time.

Pregnancy: Megace OS (Megestrol) acetate is not recommended for use during the first 4 months of pregnancy. Women should use effective birth control when taking Megace OS (Megestrol). If you become pregnant while taking Megace OS (Megestrol), tell your doctor right away.

Breast-feeding: Megace OS (Megestrol) may pass into breast milk. If you are a breast-feeding mother and are taking Megace OS (Megestrol) acetate, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using Megace OS (Megestrol) have not been established for children.