Patient Medication Information: uses, side effects, how to take - Glucophage (Sanofi-Aventis Canada, 500 mg, 850 mg)
Serious warnings and precautions box
What GLUCOPHAGE is used for:
GLUCOPHAGE is used, in addition to proper diet, exercise and weight loss, to treat high blood sugar in adults with type 2 diabetes mellitus. GLUCOPHAGE can be used by itself or in combination with other diabetes medicines.
How GLUCOPHAGE works:
GLUCOPHAGE is a medicine that contains metformin to help control your blood sugar level.
GLUCOPHAGE only helps people who already have some insulin in their bodies. It makes the insulin work better, but it can't replace insulin completely.
GLUCOPHAGE may work by creating more insulin receptors on your cells where insulin can attach and work to control blood sugar levels.
The ingredients in GLUCOPHAGE are:
Medicinal ingredient: metformin hydrochloride
Non-medicinal ingredients: magnesium stearate and povidone. Tablet coating for the 500 mg tablet includes hydroxypropyl methylcellulose, polyethylene glycol, and titanium dioxide.
GLUCOPHAGE comes in the following dosage form:
Tablets; 500 mg, 850 mg
- GLUCOPHAGE may rarely cause a serious, life-threatening condition called lactic acidosis (see Lactic Acidosis section below).
- You should not drink a lot of alcohol if you take GLUCOPHAGE (see Lactic Acidosis section below)
Do not use GLUCOPHAGE if:
- you are allergic to metformin hydrochloride any of the other ingredients in this medicine
- you have Type I diabetes mellitus that is unstable and/or insulin-dependent
- you have metabolic acidosis (when your blood becomes too acidic)
- you have diabetic ketoacidosis (when your body cannot use sugar properly and it starts breaking down fat for energy instead) with or without coma
- you have had ketoacidosis with or without coma
- you have had lactic acidosis (too much acid in the blood)
- you drink a lot of alcohol (regularly drink alcohol or sometimes drink a lot of alcohol (“binge drinking”)
- you have severe liver problems
- you have kidney problems
- you are stressed, have a severe infection, or are experiencing trauma
- you have severe dehydration (have lost a lot of water from your body)
you are pregnant or planning to become pregnant
- you are breastfeeding
- you have heart system collapse (when blood circulation fails abruptly)
- you have a disease that can cause hypoxemia (low oxygen in the blood) such as when the heart and lungs do not deliver enough oxygen to the body (cardiorespiratory insufficiency).
To help avoid side effects and ensure proper use, talk to your healthcare professional before you take GLUCOPHAGE. Talk about any health conditions or problems you may have, including if you:
- are 80 years of age or older and you have not had your kidney function tested
- have liver problems
- develop a serious medical condition, such as heart attack, severe infection, or a stroke
- develop or experience a worsening of heart disease or heart failure
- have thyroid problems
- have low blood levels of vitamin B12 or calcium
Other warnings you should know about:
Low vitamin B12: GLUCOPHAGE can cause your vitamin B12 level to be low. This can cause you to feel pins and needles in your hands and feet (called peripheral neuropathy).
Lactic Acidosis: This can happen if metformin, the active ingredient in GLUCOPHAGE, builds up in your blood. It is a rare but serious side effect. The build up of lactic acid can cause serious damage and can be fatal in up to half of the people who develop it. If you experience lactic acidosis you might need to be hospitalized for treatment.
If you get the following symptoms, stop taking GLUCOPHAGE and contact a healthcare professional right away:
- Feel very weak and tired
- Have unusual muscle pain
- Have trouble breathing
- Have stomach pain with nausea and vomiting, or diarrhea
- Feel cold, especially in your arms and legs
- Feel dizzy or lightheaded
- Have a slow or irregular heartbeat
- Your medical condition suddenly changes
You have a higher chance of getting lactic acidosis if you:
- have severe kidney or liver problems,
- have congestive heart failure that requires treatment with medicines,
- are over the age of 80
- get dehydrated
- have low blood oxygen levels
- have a serious infection
- drink a lot of alcohol (very often or short-term “binge” drinking)
- have surgery
- have x-ray tests with injectable dyes or contrast agents.
- have or think you have a mitochondrial disease (a disease that is passed down at birth affecting mitochondria). For these patients, taking GLUCOPHAGE increases the risk for lactic acidosis and can lead to worsening of the mitochondrial disease.
Hypoglycemia (low blood sugar levels): GLUCOPHAGE rarely causes hypoglycemia. It can happen if you:
- are elderly
- do not eat enough
- drink alcohol
- exercise heavily and do not eat enough
- take other medications that lower blood sugar
- also have adrenal, pituitary or liver problems
Driving and using machines: Do not drive or operate machines if you develop low blood sugar (hypoglycemia).
Surgery: If you need to have major surgery, stop taking GLUCOPHAGE 2 days before the procedure. You will restart again once you are eating and drinking again as you normally would.
Scans or X-rays needing contrast dyes: If you need a scan for which contrast dye will be used, stop taking GLUCOPHAGE 2 days before the scan. Your healthcare professional will tell you when to restart after the scan.
Tests and check-ups: Before and during your treatment with GLUCOPHAGE, your healthcare professional will do blood tests. These will be repeated regularly. The results will tell you how well your liver, kidneys and thyroid are working and will measure the amount of vitamin B12 in your blood. These tests will also check how GLUCOPHAGE affects your blood and blood sugar.
Tell your healthcare professional about all the medicines you take, including any drugs, vitamins, minerals, natural supplements or alternative medicines.
The following may interact with GLUCOPHAGE:
- Other diabetes drugs such as glyburide
- A medicine used to treat malaria called quinine
- Medicines used to treat high blood pressure including nifedipine, amlodipine, felodipine, verapamil and diltiazem (calcium channel blockers) as well as ACE inhibitors
- Medicines used to lower extra fluid in the body including furosemide, triamterene and amiloride. These are also known as diuretics or water pills.
- A medicine used to treat heart failure called digoxin
- A medicine used to treat pain called morphine
- Medicines used to treat irregular heart beat such as procainamide and quinidine
- A medicine used to lower stomach acid called ranitidine
- Medicines used to treat bacterial infections such as trimethoprim, and vancomycin
- Medicines used to prevent blood clots (called “blood thinners”) including phenprocoumon and other antivitamin K anticoagulants
Medicines that can cause high blood sugar and may lead to a loss of blood sugar control including:
- Corticosteroid medicines like prednisone
- Medicines used to treat mental and emotional disorders including phenothiazines
- A thyroid hormone replacement drug called levothyroxine
- The female hormones, estrogen or estrogen plus progestogen
- Birth control medicines that are taken by mouth
- A medicine used to treat epilepsy called phenytoin
- A medicine used to prevent and treat low niacin called nicotinic acid
- Medicines used to stimulate the sympathetic nervous system called sympathomimetics
- A medicine used to treat active tuberculosis infections called Isoniazid
- Medicines for asthma such as salbutamol or formoterol
How to take GLUCOPHAGE
- Take GLUCOPHAGE exactly as your healthcare professional has told you. Check with them if you are not sure.
Take tablets with food to reduce nausea and vomiting.
Usual dose:
Your healthcare professional will tell you how much GLUCOPHAGE to take and when to take it.
Overdose:
If you take too much GLUCOPHAGE, you might feel stomach discomfort, nausea, vomiting, diarrhea, drowsiness, weakness, dizziness, malaise, and headache.
Lactic acidosis may also occur. This is a serious, life-threatening condition.
If you think you, or a person you are caring for, have taken too much GLUCOPHAGE, contact a healthcare professional, hospital emergency department, regional poison control centre or Health Canada’s toll-free number, 1-844 POISON-X (1-844-764-7669) immediately, even if there are no signs or symptoms.
Missed dose:
If you forget to take GLUCOPHAGE tablets, skip the missed dose. Take your next dose at the usual time. Do not take two doses at the same time to make up for a missed dose.
Possible side effects from using GLUCOPHAGE:
These are not all the possible side effects you may have when taking GLUCOPHAGE. If you experience any side effects not listed here, tell your healthcare professional.
- diarrhea
- nausea
- vomiting
- abdominal pain, bloating
- heartburn
- taste changes
- gas
- loss of appetite
- skin redness, itching, hives
GLUCOPHAGE can cause abnormal blood test results. Your healthcare professional will do blood tests during your treatment and will interpret the results.
Serious side effects and what to do about them
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
|---|---|---|---|
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
| Only if severe | In all cases | ||
| Only if severe | In all cases | ||
| Rare | |||
Lactic Acidosis (a build up of lactic acid in the blood that can cause death or cardiovascular mortality): feeling very weak, tired, or uncomfortable, unusual muscle pain, trouble breathing, unusual or unexpected stomach discomfort, stomach pain with nausea and vomiting, or diarrhea, feeling cold, feeling dizzy or lightheaded, | √ | ||
| suddenly developing a slow or irregular heartbeat | |||
| Pancreatitis (inflammation of the pancreas): prolonged severe abdominal pain which may be accompanied by vomiting; pain may spread out towards the back. | √ | ||
| Hemolytic anemia (when red blood cells are destroyed faster than bone marrow can replace them): fatigue, pale color, rapid heartbeat, shortness of breath, dark urine, chills, and backache. | √ | ||
| Encephalopathy (disease of the brain that severely alters thinking): muscle weakness in one area, poor decision-making or concentration, involuntary twitching, trembling, difficulty speaking or swallowing, seizures. | √ | ||
| Peripheral neuropathy (a result of damage to your peripheral nerves): gradual onset of numbness, prickling or tingling in your feet or hands, which can spread upward into your legs and arms, sharp, jabbing, throbbing, freezing or burning pain, extreme sensitivity to touch, lack of coordination and falling, muscle weakness or paralysis if motor nerves are affected. | √ | ||
| Very Rare | |||
| Mitochondrial Disease (a disease affecting energy producing components within cells): seizure, reduction in a person’s mental abilities (memory lapses, difficulty concentrating, trouble finding words or following conversations, poor judgment or decision-making, confusion), difficulty with body movements, muscle pain or | ✓ | ||
If you have a troublesome symptom or side effect that is not listed here or becomes bad enough to interfere with your daily activities, tell your healthcare professional.
Reporting side effects
You can report any suspected side effects associated with the use of health products to Health Canada by:
- Visiting the Web page on Adverse Reaction Reporting (canada.ca/drug-device-reporting) for information on how to report online, by mail or by fax; or
- Calling toll-free at 1-866-234-2345.
NOTE: Contact your healthcare professional if you need information about how to manage your side effects. The Canada Vigilance Program does not provide medical advice.
Storage
Store at room temperature (15°to 30°C) in well closed containers. Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
| Frequency/Side Effect/Symptom | Talk to your healthcare professional | Stop taking this drug and get immediate medical help | |
|---|---|---|---|
| Only if severe | In all cases | ||
| weakness, pain, numbness, migraine, deafness | |||
| Liver problems: yellowing of your skin and eyes (jaundice), right upper stomach area pain or swelling, nausea or vomiting, unusual dark urine, unusual tiredness | ✓ | ||
| Unknown | |||
| Hypothyroidism (underactive/low thyroid): weight gain, tiredness, hair loss, muscle weakness, feeling cold, dry skin, constipation, puffy face, heavier than normal or irregular menstrual periods, enlarged thyroid gland | ✓ | ||
| Photosensitivity (sensitivity to sunlight): itchy, red skin when exposed to sunlight | ✓ | ||
Keep out of reach and sight of children.
If you want more information about GLUCOPHAGE:
- Talk to your healthcare professional
- Find the full product monograph that is prepared for healthcare professionals and includes the Patient Medication Information by visiting the Health Canada Drug Product Database website (canada.ca/en/health-canada/services/drugs-health-products/drug-products/drug-product-database.html; the manufacturer’s website (https://www.sanofi.com/en/canada/); or by calling 1-800-265-7927.
Date of Authorization: 2026-04-07
®Registered trademark of Merck Santé. Used under licence