Riomet is an oral diabetes medicine that helps control blood sugar levels.

Riomet are used together with diet and exercise to improve blood sugar control in adults with type 2 diabetes mellitus.

Riomet is sometimes used together with insulin or other medications, but metformin is not for treating type 1 diabetes.

Riomet is supplied as an oral solution or an extended release oral suspension.

You should not use Riomet if you have severe kidney disease, metabolic acidosis, or diabetic ketoacidosis (call your doctor for treatment).

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

You may develop lactic acidosis, a dangerous build-up of lactic acid in your blood. Call your doctor or get emergency medical help if you have unusual muscle pain, trouble breathing, stomach pain, dizziness, feeling cold, or feeling very weak or tired.

Before taking this medicine

You should not use Riomet if you are allergic to metformin, or if you have:

• severe kidney disease; or

• metabolic acidosis or diabetic ketoacidosis (call your doctor for treatment).

If you need to have surgery or any type of x-ray or CT scan using a dye that is injected into your veins, you may need to temporarily stop taking Riomet. Be sure your caregivers know ahead of time that you are using this medication.

Tell your doctor if you have ever had:

• kidney disease (your kidney function may need to be checked before you take this medicine);

• high ketone levels in your blood or urine;

• heart disease, congestive heart failure;

• liver disease; or

• if you also use insulin, or other oral diabetes medications.

You may develop lactic acidosis, a dangerous build-up of lactic acid in your blood. This may be more likely if you have other medical conditions, a severe infection, chronic alcoholism, or if you are 65 or older. Ask your doctor about your risk.

Follow your doctor's instructions about using Riomet if you are pregnant or you become pregnant. Controlling diabetes is very important during pregnancy, and having high blood sugar may cause complications in both the mother and the baby. Tell your doctor if you become pregnant while taking Riomet.

Metformin may stimulate ovulation in a premenopausal woman and may increase the risk of unintended pregnancy. Talk to your doctor about your risk.

You should not breastfeed while using this medicine.

Riomet should not be given to a child younger than 10 years old.

Take Riomet exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Take Riomet with a meal.

Measure Riomet Oral Solution carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

Shake the Riomet ER Oral Suspension before you measure a dose. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

You may have low blood sugar (hypoglycemia) and feel very hungry, dizzy, irritable, confused, anxious, or shaky. To quickly treat hypoglycemia, eat or drink a fast-acting source of sugar (fruit juice, hard candy, crackers, raisins, or non-diet soda).

Your doctor may prescribe a glucagon injection kit in case you have severe hypoglycemia. Be sure your family or close friends know how to give you this injection in an emergency.

Blood sugar levels can be affected by stress, illness, surgery, exercise, alcohol use, or skipping meals. Ask your doctor before changing your dose or medication schedule.

Riomet is only part of a complete treatment program that may also include diet, exercise, weight control, regular blood sugar testing, and special medical care. Follow your doctor's instructions very closely.

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

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

Usual Adult Dose for Diabetes Type 2:

Initial dose: 500 mg orally twice a day or 850 mg orally once a day
Dose titration: Increase in 500 mg weekly increments or 850 mg every 2 weeks as tolerated
Maintenance dose: 2000 mg daily in divided doses
Maximum dose: 2550 mg/day

Comments: Metformin, if not contraindicated, is the preferred initial pharmacologic agent for treatment of type 2 diabetes mellitus.
Take in divided doses 2 to 3 times a day with meals; titrate slowly to minimize gastrointestinal side effects. In general, significant responses are not observed with doses less than 1500 mg/day.

Usual Pediatric Dose for Diabetes Type 2:

10 years or older:
Initial dose: 500 mg orally twice a day
Dose titration: Increase in 500 mg weekly increments as tolerated
Maintenance dose: 2000 mg daily
Maximum dose: 2000 mg daily

Comments: Take in divided doses 2 to 3 times a day with meals. Titrate slowly to minimize gastrointestinal side effects.

You should not use Riomet if you are allergic to metformin, or if you have:

• severe kidney disease; or

• metabolic acidosis or diabetic ketoacidosis (call your doctor for treatment).

If you need to have surgery or any type of x-ray or CT scan using a dye that is injected into your veins, you may need to temporarily stop taking Riomet. Be sure your caregivers know ahead of time that you are using this medication.

Tell your doctor if you have ever had:

• kidney disease (your kidney function may need to be checked before you take this medicine);

• high ketone levels in your blood or urine;

• heart disease, congestive heart failure;

• liver disease; or

• if you also use insulin, or other oral diabetes medications.

You may develop lactic acidosis, a dangerous build-up of lactic acid in your blood. This may be more likely if you have other medical conditions, a severe infection, chronic alcoholism, or if you are 65 or older. Ask your doctor about your risk.

Follow your doctor's instructions about using Riomet if you are pregnant or you become pregnant. Controlling diabetes is very important during pregnancy, and having high blood sugar may cause complications in both the mother and the baby. Tell your doctor if you become pregnant while taking Riomet.

Metformin may stimulate ovulation in a premenopausal woman and may increase the risk of unintended pregnancy. Talk to your doctor about your risk.

You should not breastfeed while using this medicine.

Riomet should not be given to a child younger than 10 years old.

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. An overdose can cause severe hypoglycemia or lactic acidosis.

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

Get emergency medical help if you have signs of an allergic reaction to Riomet: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Some people using Riomet develop lactic acidosis, which can be fatal. Get emergency medical help if you have even mild symptoms such as:

• unusual muscle pain;

• feeling cold;

• trouble breathing;

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

• stomach pain, vomiting; or

• slow or irregular heart rate.

Common Riomet side effects may include:

• low blood sugar;

• nausea, upset stomach; or

• diarrhea.

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.

Many drugs can interact with metformin, making it less effective or increasing your risk of lactic acidosis. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any medicine you start or stop using.