Generic Name: Metformin

  • What is this medication and its most common uses?

    Glucophage is a medicine used along with diet and exercise to help control high blood sugar in adults and children with type 2 diabetes. Glucophage is available as tablets and as extended-release tablets (a type of tablet that releases medicine into your body throughout the day) called Glucophage XR.

  • What should I know when beginning and continuing on this medication?

    How does this medication work?

    Glucophage can control your blood sugar by helping your body respond better to the insulin it makes naturally, decreasing the amount of sugar your liver makes, and decreasing the amount of sugar your intestines absorb.

    What are the beneficial effects of this medication and when should I begin to have results?

    What: Lowering your blood sugar to a normal level may prevent or delay potential complications associated with diabetes, such as blindness, kidney failure, or heart problems.

    When: Everyone responds differently to treatment, so try to be patient and follow your healthcare provider's directions. It is important that you take Glucophage exactly as your healthcare provider has prescribed.

    How do I know it is working?

    Check your blood sugar regularly and as your healthcare provider tells you to. Your healthcare provider will also do regular blood tests to measure your blood sugar levels and your hemoglobin A1C (measures your average blood sugar levels over a 2- to 3-month period). Stay on your prescribed diet and exercise program, as this will also affect the results of your blood tests.

  • What are the possible side effects of this medication?

    The following is not a full list of side effects. Side effects cannot be anticipated. If any develop or change in intensity, tell your healthcare provider as soon as possible. Only your healthcare provider can determine if it is safe for you to continue taking this medication.

    Glucophage can cause a life-threatening condition called lactic acidosis (a build-up of an acid in the blood). This is a medical emergency and must be treated in the hospital. Stop taking Glucophage and call your healthcare provider right away if you feel very weak or tired; have unusual muscle pain, trouble breathing, sleepiness or you sleep longer than usual; develop sudden stomach or intestinal problems with nausea, vomiting, or diarrhea; feel cold, especially in your arms and legs; experience dizziness or lightheadedness; or have a slow or irregular heartbeat.

    You have a higher chance of getting lactic acidosis if you have kidney or liver problems; have heart failure that requires treatment with medicines; drink a lot of alcohol; become dehydrated (lose a large amount of body fluids); have certain tests with dyes or contrast agents that are injected into your body; undergo surgery; or experience a heart attack, severe infection, or stroke.


    More common side effects may include: diarrhea, nausea, vomiting, gas, weakness, upset stomach, headache.

    Glucophage XR

    More common side effects may include: diarrhea, nausea, vomiting.

    Less common side effects of Glucophage and Glucophage XR may include:

    Low blood sugar with symptoms such as shaking, sweating, rapid heartbeat, changes in your vision, hunger, headache, or changes in your mood. Your risk of low blood sugar is higher if you do not eat enough, drink alcohol, or take other medicines to lower your blood sugar.

  • Who should not take this medication?

    Do not take Glucophage if you are allergic to it or any of its ingredients.

    Do not take Glucophage if you have kidney problems, or are going to receive an injection of dye or contrast agents for an x-ray procedure.

  • What should I tell my healthcare provider before I take the first dose of this medication?

    Tell your healthcare provider about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Glucophage. Also, talk to your healthcare provider about your complete medical history, especially if you have kidney, liver, or heart problems; drink alcohol frequently; or if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your healthcare provider uses. Depending on your condition and medical history, your healthcare provider may prescribe a different regimen. Do not change the dosage or stop taking your medication without your healthcare provider's approval.


    Adults: The usual starting dose is 500 milligrams (mg) twice a day or 850 mg once a day, given with meals.

    Children 10-16 years: The usual starting dose is 500 mg twice a day, with meals.

    Glucophage XR

    Adults: The usual starting dose is 500 mg once a day, with the evening meal.

    Your healthcare provider may increase your or your child's dose as needed.

    If you are also using insulin or taking another diabetes medicine called a sulfonylurea (such as glimepiride, glipizide, or glyburide), your healthcare provider may adjust the dose of these medicines.

  • How should I take this medication?

    Take Glucophage exactly as prescribed by your healthcare provider. Do not change your dose or stop taking Glucophage without first talking to your healthcare provider.

    Swallow Glucophage XR tablets whole. Do not crush, cut, dissolve, or chew the tablets.

    When you take Glucophage XR, you may see something in your stool that looks like a tablet. This is the empty shell from the tablet after the medicine has been absorbed in your body.

    While you are taking Glucophage, stay on your diet and exercise program, and check your blood sugar regularly as directed by your healthcare provider.

  • What should I avoid while taking this medication?

    Do not drink excessive amounts of alcohol while taking Glucophage. Alcohol can increase your chance of developing lactic acidosis.

  • What are the possible food and drug interactions associated with this medication?

    If Glucophage is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your healthcare provider before combining Glucophage with the following: birth control pills, blood pressure/heart medications known as calcium channel blockers (such as nifedipine), cimetidine, corticosteroids (such as prednisone), digoxin, estrogens, isoniazid, morphine, nicotinic acid, phenothiazines (such as chlorpromazine), phenytoin, procainamide, quinidine, quinine, ranitidine, thyroid medicines, trimethoprim, vancomycin, or water pills (such as amiloride, hydrochlorothiazide, or triamterene).

  • May I receive this medication if I am pregnant or breastfeeding?

    The effects of Glucophage during pregnancy and breastfeeding are unknown. Do not breastfeed while you are taking Glucophage. Tell your healthcare provider immediately if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What should I do if I miss a dose of this medication?

    If you miss a dose of Glucophage, take it as soon as you remember. However, if it is almost time for your next dose, skip the one you missed and return to your regular dosing schedule. Do not take two doses at once.

  • How should I store this medication?

    Store at room temperature.

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