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    Related terms
    • Brand Names: U.S.: Fortamet®;Glucophage®;Glucophage® XR;Glumetza®;Riomet®
    • Brand Names: Canada: Apo-Metformin®;Ava-Metformin;CO Metformin;Dom-Metformin;Glucophage®;Glumetza®;Glycon;JAMP-Metformin;JAMP-Metformin Blackberry;Med-Metformin;Mylan-Metformin;Novo-Metformin;Nu-Metformin;PHL-Metformin;PMS-Metformin;PRO-Metformin;Q-Metformin;RANT-Metformin;ratio-Metformin;Riva-Metformin;Sandoz-Metformin FC

    • It is used to lower blood sugar in patients with high blood sugar (diabetes). It may take 1 month to see the full effect.
    • It is used to stop high blood sugar (diabetes).
    • It may be used to help hormone balance.
    • Metformin lowers sugar and helps insulin work better.


    How to take

    • This drug may be used alone or with other high blood sugar (diabetes) drugs.
    • Take as you have been told, even if you are feeling better.
    • Take with or without food. Take with food if it causes an upset stomach.
    • Take long-acting products at dinner.
    • Long-acting products: Swallow whole. Do not chew, break, or crush.
    • Fortamet®: Take with a full glass of water.
    • Follow the diet and workout plan that your doctor told you about.

    Missed Dose

    • Take a missed dose as soon as you think about it.
    • If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
    • Do not take 2 doses at the same time or extra doses.
    • Do not change the dose or stop this drug. Talk with the doctor.


    • Store at room temperature.
    • Protect from water. Do not store in a bathroom or kitchen.



    • A small number of people may have more acid in their blood. Metformin may cause this. It may happen in people whose liver or kidneys do not work the right way.


    • Do not give the extended release product to a child younger than 17 years of age.
    • If you have an allergy to metformin or any other part of this drug.
    • Tell your doctor if you are allergic to any drugs. Make sure to tell about the allergy and what signs you had. This includes telling about rash; hives; itching; shortness of breath; wheezing; cough; swelling of face, lips, tongue, or throat; or any other signs.
    • If you have any of these health problems: Acidic blood problem, drink too much alcohol, fluid loss, kidney disease, or liver disease.
    • If you are having an x-ray with dye.


    • Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
    • Wear disease medical alert ID (identification).
    • Do not run out of this drug.
    • Stop this drug for 2 days after you have an x-ray with dye.
    • Use care if you are having surgery, if you have had a heart attack, bad infection, or stroke, or if you are 80 years of age or older and have not had your kidney function tested.
    • If you have lung disease, talk with your doctor.
    • If you have a weak heart, talk with your doctor.
    • Check your blood sugar as you have been told by your doctor.
    • Have your blood work checked often. Talk with your doctor.
    • Have an eye exam and visit the foot doctor every year.
    • Check all drugs you are taking with your doctor. This drug may not mix well with some other drugs.
    • Do not drive if your blood sugar has been low. There is a greater chance of you having a crash.
    • Avoid beer, wine, or mixed drinks.
    • Tell your doctor if you are pregnant or plan on getting pregnant.
    • Tell your doctor if you are breast-feeding.

    Side Effects

    • Low blood sugar. Signs include anger, shaking, a fast heartbeat, confusion, or sweating. Keep hard candies, glucose tablets, liquid glucose, or juice on hand for low blood sugar.
    • Belly pain.
    • Upset stomach or throwing up. Many small meals, good mouth care, sucking hard, sugar-free candy, or chewing sugar-free gum may help.
    • Loose stools (diarrhea).
    • Not hungry.
    • Bad taste in your mouth. This most often goes back to normal.
    • Too much acid in the blood (lactic acidosis) may rarely happen.

    Contact a healthcare provider

    • If you think there was an overdose, call your local poison control center or ER right away.
    • Signs of a very bad reaction to the drug. These include wheezing; chest tightness; fever; itching; bad cough; blue or gray skin color; seizures; or swelling of face, lips, tongue, or throat.
    • Very low blood sugar or very high blood sugar.
    • Very bad dizziness.
    • Trouble breathing.
    • Feeling cold.
    • Very bad belly pain.
    • Very upset stomach or throwing up.
    • Very loose stools (diarrhea).
    • A big weight loss.
    • Very bad muscle pain or weakness.
    • Feeling very tired or weak.
    • Any rash.
    • Side effect or health problem is not better or you are feeling worse.

    General Statements

    • If you have a very bad allergy, wear an allergy ID at all times.
    • Do not share your drugs with others and do not take anyone else's drugs.
    • Keep all drugs out of the reach of children and pets.
    • Most drugs may be thrown away in household trash after mixing with coffee grounds or kitty litter and sealing in a plastic bag.
    • In Canada, take any unused drugs to the pharmacy. Also, visit to learn about the right way to get rid of unused drugs.
    • Keep a list of all your drugs (prescription, natural products, vitamins, OTC) with you. Give this list to your doctor.
    • Call your doctor for help with any side effects. If in the U.S., you may also call the FDA at 1-800-FDA-1088 or if in Canada, you may also call Health Canada's Vigilance Program at 1-866-234-2345.
    • Talk with the doctor before starting any new drug, including OTC, natural products, or vitamins.

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    Copyright © 2011 Natural Standard (

    The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.

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