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metformin and sitagliptin (Janumet, Janumet XR)

Brand Names: Janumet, Janumet XR

Generic Name: metformin and sitagliptin

What is metformin and sitagliptin (Janumet, Janumet XR)?

Metformin and sitagliptin are oral diabetes medicines that help control blood sugar levels.

Metformin works by decreasing glucose (sugar) production in the liver and decreasing absorption of glucose by the intestines. Sitagliptin works by regulating the levels of insulin your body produces after eating.

Metformin and sitagliptin is a combination medicine that is used together with diet and exercise to improve blood sugar control in adults with type 2 diabetes mellitus. This medicine is not for treating type 1 diabetes.

Metformin and sitagliptin may also be used for purposes not listed in this medication guide.

What are the possible side effects of metformin and sitagliptin (Janumet, Janumet XR)?

Get emergency medical help if you have signs of an allergic reaction (hives, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning in your eyes, skin pain, red or purple skin rash that spreads and causes blistering and peeling).

Stop taking this medicine and call your doctor right away if you have symptoms of pancreatitis: severe pain in your upper stomach spreading to your back, nausea and vomiting, loss of appetite, or fast heartbeats.

Some people using metformin 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
  • irregular heart rate.

Call your doctor at once if you have any of these serious side effects:

  • severe autoimmune reaction--itching, blisters, breakdown of the outer layer of skin;
  • severe or ongoing pain in your joints;
  • little or no urinating; or
  • symptoms of heart failure--shortness of breath (even while lying down), swelling in your legs or feet, rapid weight gain.

Common side effects may include:

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.

What is the most important information I should know about metformin and sitagliptin (Janumet, Janumet XR)?

You should not use this medicine if you have severe kidney disease or diabetic ketoacidosis (call your doctor for treatment).

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.

What should I discuss with my healthcare provider before taking metformin and sitagliptin (Janumet, Janumet XR)?

You should not use this medicine if you are allergic to metformin or sitagliptin (Januvia), or if you have severe kidney disease or diabetic ketoacidosis (call your doctor for treatment with insulin).

Tell your doctor if you have ever had:

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.

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 will need to temporarily stop taking metformin and sitagliptin. Be sure your caregivers know ahead of time that you are using this medication.

Follow your doctor's instructions about using this medicine if you are pregnant or breast-feeding a baby. Blood sugar control is very important during pregnancy, and your dose needs may be different during each trimester of pregnancy. Your dose needs may also be different while you are breast-feeding.

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

This medicine is not approved for use by anyone younger than 18 years old.

How should I take metformin and sitagliptin (Janumet, Janumet XR)?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Use the medicine exactly as directed.

Take metformin and sitagliptin with meals.

Swallow the tablet whole and do not crush, chew, or break it.

Some tablets are made with a shell that is not absorbed or melted in the body. Part of this shell may appear in your stool. This is normal and will not make the medicine less effective.

Call your doctor if you see a tablet in your stool several times.

Low blood sugar (hypoglycemia) can happen to everyone who has diabetes. Symptoms include headache, hunger, sweating, irritability, dizziness, nausea, and feeling shaky. To quickly treat low blood sugar, always keep a fast-acting source of sugar with you such as fruit juice, hard candy, crackers, raisins, or non-diet soda.

Your doctor can prescribe a glucagon emergency injection kit to use in case you have severe hypoglycemia and cannot eat or drink. Be sure your family and close friends know how to give you this injection in an emergency.

Also watch for signs of high blood sugar (hyperglycemia) such as increased thirst or urination, blurred vision, headache, and tiredness.

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.

Metformin and sitagliptin 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 and heat.

What happens if I miss a dose (Janumet, Janumet XR)?

Take the medicine (with food) 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.

What happens if I overdose (Janumet, Janumet XR)?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222. You may have severely low blood sugar (extreme weakness, nausea, tremors, sweating, confusion, trouble speaking, fast heartbeats, or seizure).

What should I avoid while taking metformin and sitagliptin (Janumet, Janumet XR)?

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

What other drugs will affect metformin and sitagliptin (Janumet, Janumet XR)?

Many drugs can affect metformin and sitagliptin, making this medicine 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.

Where can I get more information (Janumet, Janumet XR)?

Your pharmacist can provide more information about metformin and sitagliptin.


Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. 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. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

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Reviewed on 12/19/2018

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