Metformin oral tablets dosage: A detailed guide

This article describes metformin’s dosages, strengths, and details on how to take it. You’ll also find information on cost savings and coupon options for metformin.

Metformin immediate-release oral tablets are a generic medication and don’t come in a brand-name version. Metformin extended-release oral tablets are a generic medication of the brand names Fortamet and Glumetza. The different forms of metformin are described in detail below.

If you want to know more about metformin, see this overview article. It covers details about the drug’s uses, side effects, ways to save on cost, and more.

Boxed warning: Risk of lactic acidosis

Metformin has a boxed warning for the risk of lactic acidosis. Boxed warnings are serious warnings from the Food and Drug Administration (FDA). See the end of this article for more information.

Forms and strengths of metformin

Metformin oral tablets come as follows:

• Forms:
  • immediate-release tablets that you swallow
  • extended-release tablets that you swallow

With the immediate-release form, the drug starts working as soon as you swallow the tablet. With the extended-release form, the drug works over time after you swallow the tablet.

• Strengths:
  • immediate-release tablets:
    • 500 milligrams (mg)
    • 850 mg
    • 1,000 mg
  • extended-release tablets:
    • 500 mg
    • 750 mg
    • 1,000 mg

Dosage of metformin

This article describes the usual recommended dosages* for metformin oral tablets.

If your doctor prescribes this medication, they’ll determine the dosage that’s best for you. Do not change your dosage of metformin oral tablets without your doctor’s recommendation.

* The drugmaker provides these recommended dosages. If your doctor prescribes metformin, be sure to take the dosage they prescribe for you.

Usual recommended dosages of metformin in adults

Usually, doctors start by prescribing a low dosage of metformin oral tablets. Then, they’ll adjust the dosage over time until the right dosage is reached. Ultimately, your doctor will prescribe the lowest dose of metformin oral tablets that gives the desired outcome.

The information below describes commonly prescribed dosages. That said, always take the dosage your doctor prescribes for you. There is no “normal” dosage of metformin. Your doctor will determine the dosage that best meets your needs.

Dosage chart to help manage blood sugar levels in adults with type 2 diabetes

Metformin oral tablets are prescribed for managing blood sugar levels in adults with type 2 diabetes. The dosage of metformin oral tablets your doctor prescribes for you depends on the form you’re taking and other factors. (For details on how to take your dose(s), see the “How metformin is taken” section below.)

The dosage chart below compares the recommended dosages for the immediate-release and extended-release metformin oral tablets in milligrams (mg):

* For immediate-release tablets, your doctor may increase your dose by 500 mg per week or 850 mg every 2 weeks, up to the maximum dosage.
† For extended-release tablets, your doctor may increase your dose by 500 mg per week, up to the maximum dosage.

Dosages of metformin in children

Metformin oral tablets are prescribed for children ages 10 to 17 years with type 2 diabetes. The recommended dosage for metformin immediate-release oral tablets is 500 mg twice per day. The doctor may increase their dose by 500 mg per week until the right dosage is reached. The maximum dose per day is 2,000 mg, divided into two to three doses.

Metformin extended-release tablets are not approved for use in children.

For more information about metformin dosages in children, talk with your child’s doctor. (For details on how to give your child metformin oral tablets, see the “How metformin is taken” section below.)

Dosage adjustments for metformin

Your doctor will prescribe a dosage of metformin oral tablets based on several factors, including:

• the specific condition being treated and how severe it is
• your age
• other health conditions you may have
• how your body responds to metformin

Missed dose of metformin

Talk with your doctor or pharmacist about any missed doses of metformin oral tablets. They can recommend whether you should take the missed dose or skip it and take your next dose as scheduled. Usually, they’ll advise you to skip the missed dose. You should not take an extra dose the next day to make up for the missed dose.

For tips on how to plan your doses of metformin oral tablets and avoid missing a dose, read this article. You could also try downloading a reminder app on your phone or setting an alarm.

How metformin is taken

Metformin oral tablets are taken by mouth with meals. You’ll swallow the tablets whole. Metformin extended-release tablets should not be crushed, broken, or chewed. Doing so can increase your risk of side effects. (To learn more about the side effects of metformin, see this article.)

Your doctor may advise you to divide your metformin dosage. For example, if your dosage is 1,000 milligrams (mg) per day, they may ask you to take one 500 mg tablet in the morning and one 500 mg tablet in the evening. The frequency depends on the form and strength of metformin oral tablets your doctor prescribes for you. It also depends on how your body responds to the drug.

In certain cases, your doctor may recommend that you take immediate-release metformin three times per day. Always take your metformin oral tablets exactly as your doctor prescribes.

Your doctor may also advise that you take this medication around the same time(s) each day. This can help the drug work more effectively because it keeps a consistent amount of the drug in your body. For what to expect while taking metformin, read this article.  

If it’s hard for you to swallow medication tablets, view this article. You’ll find suggestions on how to swallow medications that come in pill form.

Also, be sure to talk with your doctor or pharmacist. They can offer recommendations about taking your medication.

Metformin coupon

Visit this page to access Optum Perks coupons and get price estimates for metformin when you use the coupons. These coupons can provide significant savings on your prescription costs.

Note: Optum Perks coupons cannot be used with any insurance copays or benefits.

Frequently asked questions

Below are answers to some commonly asked questions about metformin oral tablets and its dosage.

Is metformin prescribed for weight loss? If it is, what’s the metformin dosage for weight loss?

Metformin isn’t approved for weight loss. So there isn’t a recommended dosage for weight loss in nondiabetic people.

Prescribing metformin for weight management would be considered an off-label use. (With off-label use, doctors prescribe a drug for a purpose other than what it’s approved for.)

Metformin is approved to help manage blood sugar levels in people with type 2 diabetes. Metformin lowers blood sugar levels, which means there’s less glucose (blood sugar) available to be stored as fat. So some people taking metformin may experience weight loss. For more information about weight loss and metformin, read this article.

If you’d like information about weight management while taking metformin, talk with your doctor.

Do doctors prescribe metformin to treat prediabetes? If so, what’s the metformin dosage for prediabetes?

Metformin isn’t approved to treat prediabetes. So there’s no recommended metformin dosage for prediabetes. Metformin is approved to help lower blood sugar levels in people with type 2 diabetes.

With prediabetes, your blood sugar is higher than usual. But it’s not at a high enough level for you to have type 2 diabetes. Prediabetes may develop into type 2 diabetes.

The American Diabetes Association recommends metformin for off-label treatment of prediabetes in some people. (With off-label use, doctors prescribe a drug for a purpose other than what it’s approved for.)

For information about metformin and prediabetes, talk with your doctor.

Does metformin treat PCOS? If it does, what metformin dosage is used for PCOS?

Metformin isn’t approved to treat polycystic ovary syndrome (PCOS). (This condition affects hormone levels in females* and is linked to type 2 diabetes.) Taking metformin for this purpose would be considered off-label use. (With off-label use, doctors prescribe a drug for a purpose other than what it’s approved for.)

For information about metformin and PCOS, talk with your doctor.

* Sex and gender exist on spectrums. In this article, we use the term “female” to refer to a person’s sex assigned at birth.

Is there a recommended dosage of metformin for anti-aging purposes?

No, there isn’t a recommended dosage of metformin for aging. Metformin isn’t approved for this use. But some research shows that managing weight, blood sugar, blood pressure, and cholesterol may increase life expectancy. And since doctors prescribe metformin together with exercise and a balanced diet to manage blood sugar, it may help increase life expectancy.

To learn more about slowing age-related diseases, talk with your doctor.

Is metformin used long term?

Yes, doctors usually prescribe metformin oral tablets as a long-term treatment.

If you and your doctor determine that it’s safe and effective for your condition, you’ll likely take it long term.

Overdose of metformin

It’s important that you do not take more metformin oral tablets than your doctor prescribes. Doing so can lead to serious side effects.

For instance, some people have experienced lactic acidosis (a buildup of lactic acid in your blood) with metformin overdose. Metformin has a boxed warning about lactic acidosis. A boxed warning is a serious warning from the Food and Drug Administration (FDA). To learn more about metformin’s boxed warning, see the “Boxed warning: Risk of lactic acidosis” section above.

For more information about metformin side effects, read this article or talk with your doctor.

What to do in case you take too much metformin

If you think you’ve taken too much metformin, call your doctor or pharmacist right away. Or you could call 800-222-1222 to speak to someone at the American Association of Poison Control Centers. You can also use its online resource. If you have severe symptoms, call 911 or a local emergency number immediately. You can also go to the closest emergency room.

What to ask your doctor

This article describes the usual recommended dosages for metformin oral tablets. If your doctor prescribes this medication, they’ll advise the dosage that’s best for you.

Do not change your dosage of metformin oral tablets without your doctor’s recommendation. You should take metformin oral tablets exactly as your doctor prescribes. Check out the recommended dosages in the “Dosage of metformin” section above.

Let your doctor know if you have concerns or questions about your treatment plan.

Here’s a list of some possible questions you may want to ask your doctor:

• Why are the dosage recommendations for metformin immediate-release and extended-release tablets different?
• Will you change my dosage if I have bothersome side effects from metformin?
• Why isn’t there an extended-release dosage form for children?
• If I have kidney or liver problems, will you adjust my dosage of metformin?

Boxed warning: Risk of lactic acidosis

Metformin has a boxed warning for the risk of lactic acidosis. Boxed warnings are serious warnings from the Food and Drug Administration (FDA).

Lactic acidosis is a serious condition in which there’s a buildup of lactic acid in your blood. It’s a rare side effect but can be life threatening. Lactic acidosis is a medical emergency that needs to be treated in a hospital.

Your doctor will monitor you for symptoms of lactic acidosis while you’re taking metformin. Symptoms of lactic acidosis include trouble breathing, weakness, extreme sleepiness, dizziness, slow heart rate, and feeling cold.

People with kidney or liver problems have a higher risk of lactic acidosis while taking metformin. Drinking alcohol or taking other drugs while taking metformin also increase the risk.

For more information about this boxed warning, talk with your doctor or pharmacist.

Disclaimer: Optum Perks has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.