Glucophage (Metformin)

(℞) Prescription Required

    Glucophage (Metformin) Dosage and Side Effects

    GLUCOPHAGE (metformin hydrochloride) is used to treat type 2 diabetes which cannot be controlled by proper diet, exercise and weight reduction.

    Warnings and Precautions

    Serious Warnings and Precautions

    GLUCOPHAGE may rarely cause a serious, life-threatening condition called lactic acidosis.

    You should not take GLUCOPHAGE due to greater risk for lactic acidosis if you:

    • have kidney problems
    • are 80 years or older and you have NOT had your kidney function tested
    • are seriously dehydrated (have lost a lot of water from your body)
    • have liver disease
    • drink a lot of alcohol (regularly drink alcohol or sometimes drink a lot of alcohol, binge drinking)
    • have an x-ray procedure with injection of dyes (contrast agents)
    • prior to surgery or during recovery phase
    • develop a serious medical condition, such as heart attack, severe infection, or a stroke

    Due to greater risk for lactic acidosis, you should talk to your doctor if you take GLUCOPHAGE and if you:

    • develop or experience a worsening of heart disease and particularly heart failure

    Signs and symptoms of lactic acidosis include: discomfort, muscle pain, difficult or fast breathing, extreme tiredness, weakness, upset stomach, stomach pain, feeling cold, low blood pressure or slow heartbeat.

    If any of the above side effects occur, consult your doctor immediately.

    Tell your doctor if you are pregnant or plan to become pregnant. GLUCOPHAGE should not be used during pregnancy and insulin treatment is recommended during pregnancy. Talk with your doctor about your choices. You must not take GLUCOPHAGE if you are nursing a child.

    Tell your doctor of any other medical condition including: vitamin B12 deficiency or anemia, excessive alcohol use, allergies.

    Do not start or stop any medicine without doctor or pharmacist approval.

    Side Effects

    Common side effects of GLUCOPHAGE include:

    • diarrhea
    • nausea
    • upset stomach
    • abdominal bloating
    • gas
    • loss of appetite

    These side effects generally go away after you take the medicine for a while. Taking your medicine with meals can help reduce these side effects. Tell your doctor if the side effects bother you a lot, last for more than a few weeks, come back after they've gone away, or start later in therapy. You may need a lower dose or need to stop taking the medicine for a short period or for good.

    GLUCOPHAGE rarely cause hypoglycemia (low blood sugar) by themselves. However, hypoglycemia can happen if you do not eat enough, if you drink alcohol, or if you take other medicines to lower blood sugar.

    Lactic Acidosis. In rare cases, GLUCOPHAGE can cause a serious side effect called lactic acidosis. This is caused by a buildup of lactic acid in your blood. This build-up can cause serious damage. Lactic acidosis caused by GLUCOPHAGE is rare and has occurred mostly in people whose kidneys were not working normally. Although rare, if lactic acidosis does occur, it can be fatal in up to half the people who develop it.

    It is also important for your liver to be working normally when you take GLUCOPHAGE. Your liver helps remove lactic acid from your blood.

    Make sure you tell your doctor before you use GLUCOPHAGE if you have kidney or liver problems.

    You should also stop using GLUCOPHAGE and call your doctor right away if you have signs of lactic acidosis. Lactic acidosis is a medical emergency that must be treated in a hospital.

    If your medical condition suddenly changes, stop taking GLUCOPHAGE and call your doctor right away. This may be a sign of lactic acidosis or another serious side effect.

    Interactions with this medication

    Some drugs may interact with GLUCOPHAGE. Careful monitoring is advised. Tell your doctor if you are taking:

    • other diabetes drugs such as glyburide
    • furosemide
    • nifedipine
    • cationic drugs (e.g., amiloride, digoxin, morphine, procainamide, quinidine, quinine, ranitidine, triamterene, trimethoprim, and vancomycin)
    • other drugs tend to produce hyperglycemia (high blood sugar) and may lead to a loss of blood sugar control. Some example of drugs that can increase the blood sugar include:
      • Thiazide and other diuretics (water pills)
      • Corticosteroids
      • Phenothiazines
      • Thyroid products
      • Estrogens or estrogens plus progestogen
      • Oral contraceptives
      • Phenytoin
      • Nicotinic acid
      • Sympathomimetics
      • Calcium channel blocking drugs
      • Isoniazid
      • Beta-2-agonists
    • ACE inhibitors drugs may lower blood glucose and the combination with GLUCOPHAGE should be carefully monitored.

    Before using any drugs or herbal products, check with your doctor or your pharmacist.

    Proper Use of this medication

    Usual dose:

    Your doctor will tell you how much medicine to take and when to take it. Follow the directions provided by your doctor for using this medicine. Taking this medicine with food will decrease symptoms such as nausea and vomiting.


    In general, an overdose may lead to increased symptoms as described under Side Effects and What to Do About Them: including stomach discomfort, nausea, vomiting, diarrhea, drowsiness, weakness, dizziness, malaise and headache.

    A serious, life-threatening condition called lactic acidosis may also occur (see Warnings and Precautions, Lactic Acidosis:).

    If you have taken too much GLUCOPHAGE, immediately see your doctor, contact the poison control or go to the nearest hospital emergency department. Do this even if there are no signs of discomfort or poisoning.

    Missed dose:

    If you forget to take GLUCOPHAGE tablets, do not take a double dose to make up for forgotten individual doses. Take the next dose at the usual time.

    Other related products

    The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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