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Generic Name: metformin and sitagliptin (met FOR min and SI ta glip tin)
Brand Names: Janumet, Janumet XR

What is Janumet?

Janumet contains a combination of metformin and sitagliptin. 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.

Janumet is used to treat type 2 diabetes.

Janumet is not for treating type 1 diabetes.

Important information

You should not use Janumet if you have liver or kidney disease, or if you are in a state of diabetic ketoacidosis (call your doctor for treatment with insulin).

Slideshow: 10 Things to Know About Metformin

Janumet may cause a serious condition called lactic acidosis. 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, fast or uneven heart rate, dizziness, or feeling very weak or tired.

Before taking this medicine

You should not use Janumet if you are allergic to metformin (Actoplus Met, Avandamet, Fortamet, Glucophage, Riomet) or sitagliptin (Januvia), if you have kidney disease, or if you are in a state of diabetic ketoacidosis (call your doctor for treatment with insulin).

Some people taking metformin develop a serious condition called lactic acidosis. This may be more likely 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 risk.

To make sure Janumet is safe for you, tell your doctor if you have:

  • liver disease;

  • a history of heart disease;

  • pancreatitis;

  • high triglycerides (a type of fat in the blood);

  • gallstones;

  • a history of alcoholism; or

  • if you are over 80 years old and have not recently had your kidney function checked.

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 Janumet. Be sure your caregivers know ahead of time that you are using this medication.

Janumet is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

It is not known whether metformin and sitagliptin passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

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

How should I take Janumet?

Take Janumet exactly as prescribed by your doctor. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended. Your blood sugar will need to be checked often, and you may need other blood tests at your doctor's office.

Take Janumet with meals.

Do not crush, chew, or break an extended-release tablet. Swallow it whole.

Janumet tablets may not completely dissolve in the body. Part of the tablet may appear in your stool. This is a normal side effect of Janumet 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, pale skin, irritability, dizziness, feeling shaky, or trouble concentrating. Always keep a source of sugar with you in case you have low blood sugar. Sugar sources include fruit juice, hard candy, crackers, raisins, and non-diet soda. Be sure your family and close friends know how to help you in an emergency.

If you have severe hypoglycemia and cannot eat or drink, use a glucagon injection. Your doctor can prescribe a glucagon emergency injection kit and tell you how to use it.

Check your blood sugar carefully during times of stress, travel, illness, surgery or medical emergency, vigorous exercise, or if you drink alcohol or skip meals. These things can affect your glucose levels and your dose needs may also change. Do not change your medication dose or schedule without your doctor's advice.

Janumet is only part of a complete program of treatment that may also include diet, exercise, weight control, foot care, and eye care. Follow your diet, medication, and exercise routines very closely.

Store Janumet at room temperature away from moisture and heat.

Janumet dosing information

Usual Adult Dose of Janumet for Diabetes Type 2:

Dose should be individualized based on patient's current regimen, effectiveness, and tolerability.
Maximum dose: Metformin 2000 mg-sitagliptin 100 mg orally daily

Janumet immediate release:
-Patients not currently treated with metformin: Metformin 500 mg-sitagliptin 50 mg orally twice a day

-Patients already treated with metformin: Sitagliptin 50 mg and the dose of metformin previously prescribed (500 mg or 1000 mg) orally twice a day. Metformin 1000 mg-sitagliptin 50 mg orally twice a day is recommended for patients already taking metformin 850 mg orally twice a day.

Janumet extended release:
-Patients not currently treated with metformin: Metformin 1000 mg-sitagliptin 100 mg orally once a day

-Patients already treated with metformin: Sitagliptin 100 mg and the dose of metformin previously prescribed (500 mg or 1000 mg) once a day. For patients taking metformin immediate-release 850 mg or 1000 mg twice a day, the recommended dose is two tablets of sitagliptin metformin 1000 mg-50 mg sitagliptin taken together once a day.

Patients changing between immediate-release and extended-release: Maintain the same daily dose of metformin-sitagliptin

Comments: Co-administration of metformin-sitagliptin with an insulin secretagogue (e.g., sulfonylurea) or insulin may require lower doses of insulin secretagogue or insulin to reduce the risk of hypoglycemia.

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. You may have signs of low blood sugar, such as extreme weakness, blurred vision, sweating, trouble speaking, tremors, stomach pain, confusion, and seizure (convulsions).

What should I avoid while taking Janumet?

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

Janumet side effects

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

Stop taking Janumet 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 develop lactic acidosis while taking metformin. Early symptoms may get worse over time and this condition can be fatal. Stop taking Janumet and 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;

  • 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 of these serious side effects:

  • severe or ongoing pain in your joints;

  • little or no urinating;

  • shortness of breath (even with mild exertion), swelling in your hands or feet, rapid weight gain; or

  • severe skin reaction - fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Common Janumet side effects may include:

  • upset stomach, gas, diarrhea, nausea, vomiting;

  • headache, weakness; or

  • cold symptoms such as runny or stuffy nose, sneezing, sore throat.

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 Janumet?

Other drugs may increase or decrease the effects of Janumet on lowering your blood sugar. Tell your doctor about all medications you use. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your pharmacist can provide more information about Janumet.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Janumet 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. 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 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.

Copyright 1996-2015 Cerner Multum, Inc. Version: 6.05. Revision Date: 2015-09-09, 2:47:33 PM.