Glumetza (Metformin) – Oral

Warning:

Metformin-associated lactic acidosis has caused a fast drop in body temperature (hypothermia), low blood pressure (hypotension), an unusually slow heartbeat (bradyarrhythmia), and death. The first symptoms of metformin-associated lactic acidosis can be subtle, and may include fatigue and pain, trouble breathing, tiredness, and stomach pain. Metformin-associated lactic acidosis usually creates high blood lactate levels (greater than 5 millimoles per liter, or mmol/L), anion gap acidosis (with no evidence of ketonemia or ketonuria), a high lactate/pyruvate ratio, and plasma levels of metformin that are greater than 5 micrograms to milliliters (mcg/ml). If lactic acidosis is suspected, stop using Glumetza and seek medical attention immediately.

What Is Glumetza?

Glumetza is a brand of metformin hydrochloride (another is Glucophage). Glumetza comes in an extended-release oral tablet and is used to treat high blood sugar in type 2 diabetes mellitus (T2DM). Glumetza is a prescription-only medicine that belongs to the biguanide medication class. It treats type 2 diabetes by decreasing glucose (sugar) production in your liver, decreasing absorption of glucose in your intestines, and improving insulin sensitivity by increasing your body’s uptake and use of glucose.

Drug Facts

Generic Name: Metformin hydrochloride

Brand Name(s): Glumetza

Drug Availability: Prescription

Therapeutic Classification: Biguanide

Available Generically: Yes

Controlled Substance: No

Administration Route: Oral

Active Ingredient: Metformin hydrochloride (N,N-dimethylimidodicarbonimidic diamide hydrochloride)

Dosage Form(s): Tablet, solution, extended release tablet, suspension, extended release suspension, 24 HR

What Is Glumetza Used For?

Glumetza is used to treat high blood sugar in type 2 diabetes mellitus (T2DM). It’s usually prescribed, like other forms of metformin, as the first line of treatment for people with type 2 diabetes that hasn’t responded yet to treatment by diet and exercise alone. Depending on the severity of your disease, metformin can be used along with other medicines to control your blood sugar (blood glucose) and improve your hemoglobin A1C (HbA1c) level.

How to Take Glumetza

Glumetza comes in an extended-release oral tablet (500 mg tablet or 1,000 milligram tablet). If you’re taking Glumetza for the first time, the starting dose is usually 500 milligrams by mouth once a day with your evening meal. Depending on how your body adjusts to the medicine over one to two weeks, your healthcare provider may increase your dose 500 milligrams at a time until you reach the best level of glucose control for you.

The maximum dose is 2,000 milligrams by mouth per day. Extended-release metformin should generally be taken with the evening meal. Please take this medicine as directed by your healthcare provider. 

Glumetza tablets must be swallowed whole and never split, cut, crushed, or chewed. Tell your healthcare provider if you can’t swallow tablets whole. Your healthcare provider may prescribe a different medicine for you.

Your healthcare provider should do blood tests to check how well your kidneys and liver are working before and during your treatment with Glumetza, as well as your blood sugar levels and HbA1c. Try your best to stay on your prescribed diet and movement/exercise program, and test your blood sugar regularly while taking this medicine.

If you’re having trouble with your diet or exercise, talk to your healthcare provider about groups that you could join or providers that can help, like a registered dietitian nutritionist (RD or RDN) with certification as a certified diabetes care and education specialist (CDCES).

Avoid excess amounts of alcohol while taking this medicine.

Storage

Metformin hydrochloride should be stored in a dry area at room temperature (68 and 77 degrees Fahrenheit) in a sealed container protected from light. When out of the home, Glumetza can temporarily be in temperatures ranging from 59 to 86 degrees. Keep Glumetza and all medicines out of the reach of children

How Long Does Glumetza Take to Work?

Glumetza takes about four to eight hours to fully work.

What Are the Side Effects of Glumetza?

This is not a complete list of side effects and others may occur. A medical professional can advise you on side effects. If you experience other effects, contact your pharmacist or a medical professional. You may report side effects to the FDA at www.fda.gov/medwatch or 800-FDA-1088.

Common Side Effects

Common side effects associated with Glumetza include:

  • Diarrhea
  • Nausea
  • Upset stomach or stomach pain
  • Gas
  • Indigestion
  • Low blood sugar (hypoglycemia)

Taking Glumetza with your evening meal can help decrease the common stomach side effects of metformin that usually occur at the start of treatment. If you have unexplained stomach problems, tell your healthcare provider. Stomach problems that start later during treatment may be a sign of something else possibly more serious, so do tell your healthcare provider if you have side effects that bother you or that do not go away.

Severe Side Effects

Metformin hydrochloride can cause a rare, but serious condition called lactic acidosis that can cause death (black-box warning). Lactic acidosis is a medical emergency and must be treated in a hospital.

Stop taking Glumetza and notify your healthcare provider right away if you get any of the following symptoms of lactic acidosis:

  • Feel very weak or tired
  • Have uabnormal muscle pain
  • Have trouble breathing
  • Have unusual sleepiness or sleep longer than usual
  • Have unexplained stomach or intestinal problems with nausea and vomiting, or diarrhea
  • Feel cold, especially in your arms and legs
  • Feel dizzy or light-headed
  • Have a slow or irregular heartbeat

Low blood sugar (hypoglycemia) can become a serious side effect of Glumetza if left untreated especially if you take Glumetza with other medicines that can also cause low blood sugar, such as sulfonylureas or insulin. Symptoms of low blood sugar include:

  • Change in mood
  • Change in vision
  • Headache
  • Hunger
  • Rapid heartbeat
  • Shaking
  • Sweating

Be sure to call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency.

Long-Term Side Effects

Over time, the use of Glumetza may cause low B12 levels in your body and possibly anemia. This can be reversed by either stopping Glumetza or supplementing with Vitamin B12.

Report Side Effects

Glumetza may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your provider may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

How Much Glumetza Should I Take?

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The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For type 2 diabetes:
    • For oral dosage form (extended-release tablets):
      • Adults—
        • Metformin alone (Fortamet®): At first, 1000 milligrams (mg) once a day taken with the evening meal. Your doctor may increase your dose if needed until your blood sugar is controlled. However, the dose is usually not more than 2500 mg per day.
        • Metformin alone (Glucophage® XR): At first, 500 mg once daily with the evening meal. Your doctor may increase your dose if needed until your blood sugar is controlled. However, the dose is usually not more than 2000 mg per day.
        • Metformin alone (Glumetza®): At first, 500 mg once a day taken with the evening meal. Then, your doctor may increase your dose if needed until your blood sugar is controlled. However, the dose is usually not more than 2000 mg per day.
        • Metformin with a sulfonylurea: Your doctor will determine the dose of each medicine.
        • Metformin with insulin: At first, 500 mg once a day. Then, your doctor may increase your dose by 500 mg every week if needed until your blood sugar is controlled. However, the dose is usually not more than 2500 mg per day.
      • Children—Use and dose must be determined by your doctor.
    • For oral dosage form (extended-release suspension):
      • Adults—At first, 5 milliliters (mL) once a day taken with the evening meal. Your doctor may increase your dose by 5 mL weekly if needed until your blood sugar is controlled. However, the dose is usually not more than 20 mL per day.
      • Children 10 to 16 years of age—At first, 5 mL once a day taken with the evening meal. Your doctor may increase your dose by 5 mL weekly if needed until your blood sugar is controlled. However, the dose is usually not more than 20 mL per day.
      • Children younger than 10 years of age—Use and dose must be determined by your doctor.
    • For oral dosage form (solution):
      • Adults—
        • Metformin alone: At first, 5 milliliters (mL) two times a day, or 8.5 mL once a day with meals. Your doctor may increase your dose if needed until your blood sugar is controlled. However, the dose is usually not more than 25.5 mL per day.
        • Metformin with a sulfonylurea: Your doctor will determine the dose of each medicine.
        • Metformin with insulin: At first, 5 mL once a day. Your doctor may increase your dose if needed until your blood sugar is controlled. However, the dose is usually not more than 25 mL per day.
      • Children 10 to 16 years of age—At first, 5 mL two times a day with meals. Your doctor may increase your dose if needed until your blood sugar is controlled. However, the dose is usually not more than 20 mL per day.
      • Children younger than 10 years of age—Use and dose must be determined by your doctor.
    • For oral dosage form (tablets):
      • Adults—
        • Metformin alone: At first, 500 milligrams (mg) two times a day taken with the morning and evening meals, or 850 mg a day taken with the morning meal. Your doctor may increase your dose if needed until your blood sugar is controlled. Later, your doctor may want you to take 500 or 850 mg two to three times a day with meals. However, the dose is usually not more than 2550 mg per day.
        • Metformin with a sulfonylurea: Your doctor will determine the dose of each medicine.
        • Metformin with insulin: At first, 500 mg a day. Your doctor may increase your dose by 500 mg every week if needed until your blood sugar is controlled. However, the dose is usually not more than 2500 mg per day.
      • Children 10 to 16 years of age—At first, 500 mg two times a day taken with the morning and evening meals. Your doctor may increase your dose if needed until your blood sugar is controlled. However, the dose is usually not more than 2000 mg per day.
      • Children younger than 10 years of age—Use and dose must be determined by your doctor.

Modifications

Careful monitoring of kidney function is important in individuals over the age of 65 years who take Glumetza. Glumetza treatment should be avoided in patients 80 years old or older unless their kidney function is healthy. This is to help avoid lactic acidosis.

Glumetza is generally not recommended in patients 0 to 18 years of age.  

Glumetza is not recommended in individuals who are pregnant. 

According to rat studies, Glumetza is excreted in breast milk. There may be a risk of too low blood sugar in nursing infants if you are breastfeeding and taking Glumetza. Talk with your healthcare provider about Glumetza during breastfeeding.

Missed Dose

If you miss your dose of Glumetza, skip the missed dose and resume your normal dosing schedule unless your healthcare provider tells you otherwise. Do not take extra medicine to make up for a missed dose.

Overdose: What Happens If I Take Too Much Glumetza?

Overdose symptoms of Glumetza may include:

  • Severe lactic acidosis
  • Confusion
  • Feelings of depression
  • A fast drop in body temperature (hypothermia)
  • Low blood pressure (hypotension)
  • Kidney (renal) failure may develop

What Happens If I Use Too Much Glumetza?

If you think you or someone else may have overdosed on Glumetza, call a healthcare provider or the Poison Control Center (800-222-1222).

If someone collapses or isn't breathing after taking Glumetza, call 911 immediately.

Precautions

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It is very important that your doctor check your or your child's progress at regular visits, especially during the first few weeks that you take this medicine. Blood and urine tests may be needed to check for unwanted effects.

This medicine may interact with the dye used for an X-ray or CT scan. Your doctor should advise you to stop taking it before you have any medical exams or diagnostic tests that might cause less urine output than usual. You may be advised to start taking the medicine again 48 hours after the exams or tests if your kidney function is tested and found to be normal.

Make sure any doctor or dentist who treats you knows that you are using this medicine. You may need to stop using this medicine several days before having surgery or medical tests.

It is very important to carefully follow any instructions from your health care team about:

  • Alcohol—Drinking alcohol may cause severe low blood sugar. Discuss this with your health care team.
  • Other medicines—Do not take other medicines unless they have been discussed with your doctor. This especially includes nonprescription medicines such as aspirin, and medicines for appetite control, asthma, colds, cough, hay fever, or sinus problems.
  • Counseling—Other family members need to learn how to prevent side effects or help with side effects if they occur. Also, patients with diabetes may need special counseling about diabetes medicine dosing changes that might occur with lifestyle changes, such as changes in exercise or diet. Counseling on birth control and pregnancy may be needed because of the problems that can occur in pregnancy for patients with diabetes.
  • Travel—Keep a recent prescription and your medical history with you. Be prepared for an emergency as you would normally. Make allowances for changing time zones and keep your meal times as close as possible to your usual meal times.
  • In case of emergency—There may be a time when you need emergency help for a problem caused by your diabetes. You need to be prepared for these emergencies. It is a good idea to wear a medical identification (ID) bracelet or neck chain at all times. Also, carry an ID card in your wallet or purse that says that you have diabetes and a list of all of your medicines.

Under certain conditions, too much metformin can cause lactic acidosis. The symptoms of lactic acidosis are severe and quick to appear, and usually occur when other health problems not related to the medicine are present and are very severe, such as a heart attack or kidney failure. Symptoms of lactic acidosis include abdominal or stomach discomfort, decreased appetite, diarrhea, fast or shallow breathing, a general feeling of discomfort, severe muscle pain or cramping, and unusual sleepiness, tiredness, or weakness.

If symptoms of lactic acidosis occur, you should get immediate emergency medical help.

This medicine may cause some premenopausal women who do not have regular monthly periods to ovulate. This can increase the chance of pregnancy. If you are a woman of childbearing potential, you should discuss birth control options with your doctor.

This medicine may cause hypoglycemia (low blood sugar). This is more common when this medicine is taken together with certain medicines. Low blood sugar must be treated before it causes you to pass out (unconsciousness). People feel different symptoms of low blood sugar. It is important that you learn which symptoms you usually have so you can treat it quickly. Talk to your doctor about the best way to treat low blood sugar.

Hyperglycemia (high blood sugar) may occur if you do not take enough or skip a dose of your medicine, overeat or do not follow your meal plan, have a fever or infection, or do not exercise as much as usual. High blood sugar can be very serious and must be treated right away. It is important that you learn which symptoms you have in order to treat it quickly. Talk to your doctor about the best way to treat high blood sugar.

High blood sugar may occur if you do not exercise as much as usual, have a fever or infection, do not take enough or skip a dose of your diabetes medicine, or overeat or do not follow your meal plan.

What Are Reasons I Shouldn’t Take Glumetza?

Do not take Glumetza if:

  • You have kidney or liver problems.
  • You are allergic to the ingredient metformin hydrochloride in Glumetza or any of its ingredients.
  • You are going to get an injection of dye or contrast agents for an X-ray procedure.
  • You have a condition called metabolic acidosis or diabetic ketoacidosis (increased ketones in your blood or urine).

Glumetza will sometimes need to be stopped for a short time for certain procedures, including surgery. Please talk with your healthcare provider to see if you need to stop taking Glumetza temporarily before your procedure. 

Before starting Glumetza, you should talk with your healthcare provider if you have any of the following conditions:

  • Type 1 diabetes. Glumetza should not be used to treat people with type 1 diabetes
  • History or risk for diabetic ketoacidosis (high levels of certain acids, known as ketones, in the blood or urine)
  • Kidney problems
  • Liver problems
  • Heart problems, including congestive heart failure
  • Drink alcohol very often, or drink a lot of alcohol in short-term (binge) drinking
  • Take insulin
  • Are pregnant or planning to become pregnant
  • Are breastfeeding or plan to breastfeed

These conditions can increase your risk of developing side effects to metformin. Glumetza is not recommended in children under 18 years old.

What Other Medications Interact With Glumetza?

Carbonic anhydrase inhibitors such as Topamax (topiramate) and Diamox (acetazolamide) may increase your risk of developing lactic acidosis with Glumetza. Other interactions with Glumetza include: Lasix (furosemide), Procardia (nifedipine), and Tagamet (cimetidine).

Some drugs may increase blood sugar. This can lead to issues with blood sugar control when using Glumetza. These drugs include:

  • Calcium channel blockers
  • Corticosteroids
  • Diuretics (including but not limited to thiazide)
  • Estrogens
  • Hydra (isoniazid)
  • Niacor or Niaspan (nicotinic acid)
  • Oral contraceptives
  • Phenothiazines
  • Dilantin (phenytoin)
  • Sympathomimetics
  • Thyroid drugs

Please use these drugs with caution along with Glumetza. Please consult with your healthcare provider before starting any new medicines, especially medicines that can affect your blood sugar. 

Tell your healthcare provider about all the medicines you take, including prescription and nonprescription medicines, vitamins, and herbal supplements. Glumetza may affect the way other medicines work, and other medicines may affect how Glumetza works.

What Medications Are Similar?

Glumetza is not the only available extended-release version of metformin hydrochloride. Glucophage XR and Fortamet are other brand-name formulations of extended-release metformin. Metformin also comes in immediate-release formulations as well. The brand name of immediate-release metformin is Glucophage. Metformin also comes in a suspension form with the brand name Riomet and Riomet ER.

Frequently Asked Questions

  • What is Glumetza used for?

    Glumetza is used to treat uncontrolled high blood sugar, such as in people with type 2 diabetes.

  • How does Glumetza work?

    Glumetza is a biguanide and works to control blood sugar (glucose) by decreasing the liver’s production of glucose, decreasing intestinal absorption of glucose, and improving insulin sensitivity by increasing your body’s use of glucose.

  • What are the side effects of Glumetza?

    Some common side effects of Glumetza include nausea, indigestion, diarrhea and stomach pain. Taking Glumetza with food (typically your evening meal) can help you prevent these stomach side effects. Severe side effects of Glumetza include lactic acidosis and low blood sugar (hypoglycemia).

How Can I Stay Healthy While Taking Glumetza?

Following a balanced diet and exercising regularly are key to improving your health while taking Glumetza. A balanced diet can be defined as a diet with minimal processed foods focusing on whole fruits, vegetables, protein, grains, and dairy.

The American Diabetes Association recommends 150 minutes of exercise weekly. That could be 30 minutes a day, five times a week. It is important to take your medicine regularly to help control your type 2 diabetes. Not taking your medicine regularly can lead to worsening of your diabetes and other health issues.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended as a replacement for medical advice, diagnosis, or treatment from a healthcare professional. Consult your healthcare provider before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Food and Drug Administration. Glumetza Label.

  2. DailyMed. Glumetza.

  3. American Diabetes Association. 3. Prevention or delay of type 2 diabetes: Standard of Medical Care in Diabetes––2021. Diabetes Care. 2021. doi: https://doi.org/10.2337/dc21-S003