What is the most important Information I should know about RIOMET?

RIOMET may cause a rare, but serious condition called lactic acidosis (a buildup of an acid in the blood) that can cause death.

The risk of lactic acidosis is higher in people who take certain other drugs like topiramate or cimetidine.  Be sure to tell your doctor about all the prescription and over-the-counter medications and supplements you are taking. The risk of lactic acidosis also higher in people with  kidney or liver problems , aged 65 years or older, having an X-ray, MRI or CT scan with contrast dyes, surgery or other procedures, hypoxic states (acute congestive heart failure), and excessive alcohol intake.

Lactic acidosis is a medical emergency and must be treated in the hospital. If lactic acidosis happens, it can lead to other health problems and can be deadly. Stop taking RIOMET and call your doctor right away if you have any of the following signs of too much lactic acid in the blood (lactic acidosis) like:

  • fast breathing, fast or slow heartbeat
  • a heartbeat that does not feel normal
  • very bad upset stomach or throwing up
  • feeling very sleepy, shortness of breath
  • feeling very tired or weak
  • very bad dizziness
  • feeling cold, or muscle pain or cramps

What is RIOMET?

RIOMET (metformin hydrochloride oral solution) is an oral diabetes medicine that, along with diet and exercise, helps improve blood sugar control in adults and children with type 2 diabetes mellitus.

Who should not take RIOMET?

You should not take RIOMET if you have severe kidney disease; have a condition called metabolic acidosis, including diabetic ketoacidosis.  Diabetic ketoacidosis should be treated with insulin.

 Do not take this drug if you have a very bad infection, low oxygen, or a lot of fluid loss (dehydration).

What should I tell my doctor before taking RIOMET?

Before taking RIOMET, Tell your doctor:

If you have an allergy to metformin or any other part of this drug. If you are allergic to any drugs like this one, any other drugs, foods, or other substances. Tell your doctor about the allergy and what signs you had, like 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, kidney disease, or liver disease.

If you have had a recent heart attack or stroke.

If you are taking any prescription or over-the-counter medications or vitamins and supplements.  You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor

If you are having an exam or test with contrast dye or have had one within the past 48 hours of ifyou need to have any type of x-ray, MRI or CT scan using a dye that is injected into your veins, you will need to temporarily stop taking RIOMET.

If you are not able to eat or drink like normal, including before certain procedures or surgery.

If you are pregnant or planning to become pregnant talk to your doctor about the best way to control your blood sugar levels while pregnant. Blood sugar control is very important during pregnancy, and your dose needs may be different during each trimester of pregnancy. Tell your doctor if you become pregnant while taking RIOMET.  RIOMET should not be used during pregnancy unless clearly needed.

If you are breastfeeding. It is not known if RIOMET passes into breast milk or if it could harm a nursing baby. You should not breast-feed while using this medicine.

What should I avoid while taking RIOMET?

Do not drink a lot of alcoholic drinks while taking RIOMET. This means you should not binge drink for short periods, and you should not drink a lot of alcohol on a regular basis. It lowers blood sugar and may increase your risk of lactic acidosis while taking metformin.

Do not drive if your blood sugar has been low. There is a greater chance of you having a crash.

What are the side effects of RIOMET?

Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect: Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat. Very bad belly pain. Fever or chills. Sore throat.

It is common to have stomach problems like upset stomach, throwing up, or loose stools (diarrhea) when you start taking this drug. If you have stomach problems later during care, call your doctor right away. This may be a sign of an acid health problem in the blood (lactic acidosis). Low blood sugar can happen. The chance of low blood sugar may be raised when this drug is used with other drugs for high blood sugar (diabetes). Signs may be dizziness, headache, feeling sleepy, feeling weak, shaking, a fast heartbeat, confusion, hunger, or sweating. Call your doctor right away if you have any of these signs. Follow what you have been told to do if you get low blood sugar. This may include taking glucose tablets, liquid glucose, or some fruit juices.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

  • loose stools (diarrhea)
  • gas, upset stomach or throwing up
  • feeling tired or weak.

Tell your doctor if you have side effects that bother you, last for more than a few weeks, come back after they have gone away, or start later in therapy. You may need a lower dose or need to stop taking RIOMET.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088. You may also report side effects at