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Generic Name: Riomet (met FOR min)
Brand Names: Fortamet, Glucophage, Glucophage XR, Glumetza, Riomet

What is Riomet?

Riomet (metformin oral solution) is an oral diabetes medicine that helps control blood sugar levels.

Riomet oral solution is for people with type 2 diabetes. Riomet is sometimes used in combination with insulin or other medications, but it is not for treating type 1 diabetes.

Riomet may also be used for purposes not listed in this medication guide.

Important information

You should not use Riomet oral solution if you are allergic to metformin, or if you are in a state of diabetic ketoacidosis (call your doctor for treatment with insulin).

If you need to have any type of x-ray or CT scan using a dye that is injected into your veins, you will need to temporarily stop taking Riomet.

Before taking Riomet, tell your doctor if you have liver disease or a history of heart disease.

Some people develop lactic acidosis while taking Riomet. Early symptoms may get worse over time and this condition can be fatal. Get emergency medical help if you have even mild symptoms such as: muscle pain or weakness, numb or cold feeling in your arms and legs, trouble breathing, stomach pain, nausea with vomiting, slow or uneven heart rate, dizziness, or feeling very weak or tired.

Before taking this medicine

Some people develop a life-threatening condition called lactic acidosis while taking Riomet. You may be more likely to develop lactic acidosis if you have liver or kidney disease, congestive heart failure, a severe infection, if you are dehydrated, or if you drink large amounts of alcohol. Talk with your doctor about your individual risk.

You should not use Riomet if you are allergic to metformin, or if you are in a state of diabetic ketoacidosis (call your doctor for treatment with insulin).

If you need to have any type of x-ray or CT scan using a dye that is injected into your veins, you will need to temporarily stop taking Riomet.

To make sure you can safely take Riomet, tell your doctor if you have any of these other conditions:

  • liver disease; or

  • a history of heart disease.

FDA pregnancy category B. Riomet is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment. It is not known whether metformin passes into breast milk or if it could harm a nursing baby. You should not breast-feed while you are using this medicine. Riomet should not be given to a child younger than 10 years old.

See also: Pregnancy and breastfeeding warnings (in more detail)

How should I take Riomet?

Take Riomet oral solution exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label. Your doctor may occasionally change your dose to make sure you get the best results.

Riomet is taken with a meal, normally twice a day, unless your doctor tells you otherwise. Follow your doctor's instructions.

Riomet is only part of a complete program of treatment that also includes diet, exercise, and weight control. It is important to use this medicine regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.

Your blood sugar will need to be checked often, and you may need other blood tests at your doctor's office. Visit your doctor regularly.

Check your blood sugar carefully during a time of stress or illness, if you travel, exercise more than usual, drink alcohol, or skip meals. These things can affect your glucose levels and your dose needs may also change.

Your doctor may want you to stop taking Riomet for a short time if you become ill, have a fever or infection, or if you have surgery or a medical emergency.

Ask your doctor how to adjust your Riomet dose if needed. Do not change your medication dose or schedule without your doctor's advice.

Your doctor may have you take extra vitamin B12 while you are taking Riomet. Take only the amount of vitamin B12 that your doctor has prescribed.

Store Riomet oral solution at room temperature away from moisture, heat, and light.

See also: Dosage Information (in more detail)

What happens if I miss a dose?

Take the missed dose as soon as you remember (be sure to take the medicine with food). Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose of metformin may cause lactic acidosis. Get emergency medical help if you have any of these symptoms of lactic acidosis: weakness, increasing sleepiness, slow heart rate, cold feeling, muscle pain, shortness of breath, stomach pain, feeling light-headed, and fainting.

What should I avoid?

Avoid drinking alcohol. It lowers blood sugar and may increase your risk of lactic acidosis while taking Riomet.

Riomet side effects

Get emergency medical help if you have any of these signs of an allergic reaction to Riomet: hives; difficult breathing; swelling of your face, lips, tongue, or throat. Riomet may cause lactic acidosis (a build-up of lactic acid in the body, which can be fatal). Lactic acidosis can start slowly and get worse over time. Get emergency medical help if you have even mild symptoms of lactic acidosis, such as:

  • muscle pain or weakness;

  • numb or cold feeling in your arms and legs;

  • trouble breathing;

  • feeling dizzy, light-headed, tired, or very weak;

  • stomach pain, nausea with vomiting; or

  • slow or uneven heart rate.

Call your doctor at once if you have any other serious side effect such as:
  • feeling short of breath, even with mild exertion;

  • swelling or rapid weight gain; or

  • fever, chills, body aches, flu symptoms.

Less serious Riomet side effects may include:

  • headache or muscle pain;

  • weakness; or

  • mild nausea, vomiting, diarrhea, gas, stomach pain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

What other drugs will affect Riomet?

Tell your doctor about all other medicines you use, especially:

  • furosemide (Lasix);

  • nifedipine (Adalat, Procardia);

  • cimetidine (Tagamet) or ranitidine (Zantac);

  • amiloride (Midamor) or triamterene (Dyrenium);

  • digoxin (Lanoxin);

  • morphine (MS Contin, Kadian, Oramorph);

  • procainamide (Procan, Pronestyl, Procanbid);

  • quinidine (Quin-G) or quinine (Qualaquin);

  • trimethoprim (Proloprim, Primsol, Bactrim, Cotrim, Septra); or

  • vancomycin (Vancocin, Lyphocin).

You may be more likely to have hyperglycemia (high blood sugar) if you take Riomet with other drugs that can raise blood sugar, such as:

  • isoniazid;

  • diuretics (water pills);

  • steroids (prednisone and others);

  • heart or blood pressure medication (Cartia, Cardizem, Covera, Isoptin, Verelan, and others);

  • niacin (Advicor, Niaspan, Niacor, Simcor, Slo-Niacin, and others);

  • phenothiazines (Compazine and others);

  • thyroid medicine (Synthroid and others);

  • birth control pills and other hormones;

  • seizure medicines (Dilantin and others); and

  • diet pills or medicines to treat asthma, colds or allergies.

These lists are not complete and other drugs may interact with Riomet. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.

Where can I get more information?

  • Your pharmacist can provide more information about Riomet.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Riomet only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects.

Copyright 1996-2016 Cerner Multum, Inc. Version: 11.02. Revision Date: 2012-03-31 11:31:17 PM.