Janumet (sitagliptin/metformin)

Janumet and Janumet XR are brand-name prescription medications. They are approved by the Food and Drug Administration (FDA) to help manage blood sugar levels in adults with type 2 diabetes. Doctors prescribe these medications in combination with changes in diet and exercise.

Janumet and Janumet XR have certain limitations regarding their use. For details about these limitations and the uses of the medications, see the “Janumet: Uses” section below.

The following table provides key facts about Janumet.

* ER means the drug is released slowly into your body over time.

If you’re interested in taking this drug, search here to find a doctor who might prescribe it.

Janumet and Janumet XR contain the active drugs metformin and sitagliptin. This combination only comes as a brand-name medication. And it isn’t currently available as a generic drug.

A generic is an identical copy of the active drug found in a brand-name medication. Generics typically cost less than brand-name drugs.

Below, you’ll find dosages that are commonly recommended for Janumet and Janumet XR. However, you should take the dosage your doctor prescribes for you. They’ll recommend the dosage that’s best for your needs.

Most often, doctors start by prescribing a low dosage of Janumet or Janumet XR. Then, they’ll change the dosage over time to an amount that’s right for the condition being treated. Doctors typically prescribe the smallest dosage that gives the desired outcome.

The dosage of Janumet or Janumet XR that your doctor prescribes will depend on factors such as:

• your age
• any health conditions you have
• the severity of your diabetes and your treatment goals
• whether you’ve ever taken metformin and the dosage you took or are taking

Janumet is available as follows.

• Form: oral tablet
• Strengths:
  • 50 milligrams (mg) sitagliptin/500 mg metformin
  • 50 mg sitagliptin/1000 mg metformin

Janumet XR is available as follows.

• Form: extended-release (ER) oral tablet
• Strengths:
  • 50 mg sitagliptin/500 mg metformin
  • 50 mg sitagliptin/1000 mg metformin
  • 100 mg sitagliptin/1000 mg metformin

Janumet XR is an ER drug. This means that the drug is released into your body over time. This is done to lower your risk of side effects from metformin. These especially include digestive side effects, such as diarrhea and upset stomach.

Recommended dosages for Janumet and Janumet XR in adults are described below.

Recommended dosages for Janumet in adults include the following.

• Starting dosage: 50 mg sitagliptin/500 mg metformin twice per day
• Maintenance dosage: 50 mg sitagliptin/1000 mg metformin twice per day
• Maximum dosage: 100 mg sitagliptin/2000 mg metformin twice per day

Recommended dosages for Janumet XR in adults include the following.

• Starting dosage: 100 mg sitagliptin/1000 mg metformin once per day
• Maintenance dosage: 100 mg sitagliptin/1000 mg metformin to 100 mg sitagliptin/2000 mg metformin once per day
• Maximum dosage: 100 mg sitagliptin/2000 mg metformin once per day

Below are some things to consider about Janumet’s dosage.

• Missing a dose. If you miss a dose of Janumet or Janumet XR, try to take it as soon as you remember. However, if it’s nearly time for your next dose, skip the missed dose. Take the next dose at the regular time. Do not take more than one dose of Janumet or Janumet XR at once. Try these medication reminder options to help avoid missing doses. You could also set an alarm, use a timer, or download a reminder app on your phone.
• Length of treatment. Doctors typically prescribe Janumet or Janumet XR as a long-term treatment. You’ll likely take it long term if you and your doctor feel it’s safe and effective for your condition.

As with most drugs, it’s possible to have side effects with Janumet or Janumet XR. These can include some mild side effects but also some serious ones.

To learn more about Janumet and Janumet XR’s side effects, talk with your doctor or pharmacist. They may also provide information about managing certain side effects of these drugs.

Note: The Food and Drug Administration (FDA) tracks side effects of drugs it has approved. If you would like to notify the FDA about a side effect you’ve had with Janumet, you can do so through MedWatch.

Mild and serious side effects of Janumet and Janumet XR are listed below. This article does not include all of Janumet and Janumet XR’s possible side effects.

Mild side effects* of Janumet and Janumet XR may include:

• diarrhea
• headache
• low vitamin B12 level
• nausea
• pain in your abdomen
• upper respiratory infection, such as the common cold
• vomiting
• mild allergic reaction†

Most times, mild side effects of a drug go away within a few days or a couple of weeks. Talk with your doctor or pharmacist if any side effects become severe or don’t go away.

* This is not a complete list of Janumet’s mild side effects. To learn about other mild side effects of this drug, ask your doctor or pharmacist. Or you can view the prescribing information for Janumet and Janumet XR.
† To learn more about allergic reaction, see below. An allergic reaction is possible after taking Janumet or Janumet XR. However, this side effect wasn’t reported in clinical studies of Janumet or Janumet XR.

Serious side effects of Janumet and Janumet XR may include:

• bullous pemphigoid (a rare, serious skin reaction)
• heart failure
• low blood sugar level
• pancreatitis (inflammation in the pancreas)
• severe joint pain
• sudden kidney failure
• risk of lactic acidosis*
• severe allergic reaction†

Serious side effects from Janumet and Janumet XR aren’t common, but they are possible. If you have serious side effects, call your doctor right away. However, if you’re having a medical emergency or your symptoms feel life threatening, call 911 or a local emergency number.

* Janumet and Janumet XR have a boxed warning Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source for this side effect. A boxed warning alerts doctors and patients about drug effects that may be dangerous. For more information about this side effect, see the “Janumet: Precautions” section below.
† To learn more about allergic reaction, see below. An allergic reaction is possible after taking Janumet or Janumet XR. However, this side effect wasn’t reported in clinical studies of Janumet or Janumet XR.

Here are some common questions about Janumet and Janumet XR, as well as brief answers to them. If you’d like to know more about these topics, ask your doctor.

It’s possible. The price you may pay for a certain strength of Janumet or Janumet XR can depend on a few factors. These include your insurance coverage and the pharmacy you use.

If you’d like to learn more about the price you may pay for either drug, talk with your pharmacist. They can tell you more information about this for Janumet or Janumet XR.

Yes, side effects of Janumet 50 milligram (mg) sitagliptin/1,000 mg metformin are expected to be similar to those of other strengths.

You’ll likely have the same types of side effects with any strength of the drug. This is also the case for Janumet XR.

To view side effects reported in clinical studies of Janumet and Janumet XR, check out the “Janumet: Side effects” section above. You can also talk with your pharmacist or doctor to learn more.

No, Janumet and Janumet XR aren’t used for weight loss. Neither drug is approved by the Food and Drug Administration (FDA) for this use.

There are certain drugs approved by the FDA for weight loss. Some of them are also used in people with type 2 diabetes. (Keep in mind that Janumet and Janumet XR are prescribed for use in people with type 2 diabetes.)

Your doctor can provide more information about these medications and whether they may be right for you. They can also discuss other strategies for managing a weight that’s healthy for you.

Prescription drugs, such as Janumet and Janumet XR, are approved by the Food and Drug Administration (FDA) to treat certain conditions.

Janumet and Janumet XR are approved to help manage blood sugar levels in adults with type 2 diabetes. They’re prescribed for this use in combination with changes in diet and exercise.

With type 2 diabetes, your body develops insulin resistance. This is a condition in which your cells stop responding effectively to insulin.

Insulin is a hormone made by the body. It helps your cells take up sugar from the blood to use as energy or store for later. Insulin resistance prevents your cells from using sugar as effectively. In serious cases, your body can’t use insulin at all.

Insulin resistance causes your blood sugar levels to increase. Over time, untreated high blood sugar can lead to complications of diabetes. These include diabetic kidney disease and diabetic eye disease.

Symptoms of type 2 diabetes can include:

• feeling excessively hungry or thirsty
• urinating more frequently than usual
• feeling fatigued
• having abnormal sensations, such as tingling, in your hands or feet

The manufacturer of Janumet and Janumet XR has noted some limitations to the use of these drugs. These are situations in which the drug may not be prescribed.

These limitations are as follows:

• Janumet and Janumet XR should not be used to treat type 1 diabetes. If you have type 1 diabetes, talk with your doctor to learn about approved treatments for your condition.
• It’s not known whether it’s safe to take Janumet or Janumet XR if you have a history of pancreatitis (inflammation in the pancreas). For more information, see the “Janumet: Precautions” section below.

Janumet and Janumet XR are not approved for use in children. It’s not known whether these medications are safe or effective in managing blood sugar levels in children.

Talk with your child’s doctor if you’d like to learn more about medications for their condition. They can tell you more about treatments to manage blood sugar in children with type 2 diabetes.

If you’re interested in taking Janumet or Janumet XR, search here to find a doctor who might prescribe it. You can also view this type 2 diabetes appointment guide to help prepare for your appointment.

As with other medications, prices for Janumet and Janumet XR may vary. The price of these drugs will depend on factors such as:

• the pharmacy you use
• your insurance coverage

Here are some things to consider when looking into the cost of Janumet and Janumet XR.

Option for a 90-day supply. For some drugs, it’s possible to get a 90-day supply. If this option is approved by your insurance company, it can help lower the cost of Janumet or Janumet XR. It can also help you avoid frequent trips to your pharmacy. If you’d like to learn more about this option, ask your doctor, pharmacist, or insurance company.

Need for prior authorization. Before insurance coverage for Janumet is approved, your insurance company may require prior authorization. In this case, your doctor and insurance company will communicate about your prescription for Janumet or Janumet XR. Then, the insurance company will decide if the drug will be covered. To find out if you need prior authorization for Janumet, contact your insurance company.

Possible cost assistance options. Financial assistance to help lower the cost of Janumet or Janumet XR is available. A coupon for either drug may help reduce the drug’s cost. To learn more and see if you’re eligible for support, visit the manufacturer’s website. Also, check out this article to learn about ways to save on prescription drugs.

Use of a mail-order pharmacy. Janumet and Janumet XR may be dispensed through mail-order pharmacies. Getting your prescription through a mail-order pharmacy could lower its cost. It can also allow you to get the drug without leaving home. To find out more about this option, check with your doctor, pharmacist, or insurance company.

Availability of a generic form. Janumet and Janumet XR don’t come in a generic form. A generic drug is an exact copy of the active drug in a brand-name medication. Typically, generics cost less than brand-name drugs.

Doctors may prescribe drugs other than Janumet or Janumet XR for your condition. Certain drugs may work better for you than others.

Janumet and Janumet XR are used to manage blood sugar levels in people with type 2 diabetes. Here’s a summary of other drugs that doctors sometimes prescribe for type 2 diabetes.

Your doctor can tell you about other similar drugs, such as sitagliptin (Januvia) and metformin.

For additional information about alternatives to Janumet, ask your doctor. They can tell you about other medications that could be prescribed for your condition.

It’s best to talk with your doctor if you consume alcohol and are prescribed Janumet or Janumet XR.

There’s no direct interaction between Janumet or Janumet XR and alcohol. That said, consuming alcohol while taking Janumet or Janumet XR could raise your risk of serious side effects from either medication. These include pancreatitis (inflammation in the pancreas) and lactic acidosis.*

In addition, drinking alcohol could lower your blood sugar level. (Keep in mind that Janumet and Janumet XR are prescribed to manage blood sugar in people with type 2 diabetes.) This could increase your risk of severe low blood sugar if you also take Janumet or Janumet XR. In some cases, severe low blood sugar can be life threatening.

Consuming alcohol with Janumet or Janumet XR could also affect how well the drug helps manage your blood sugar. This is because alcohol can also change your blood sugar level.

If you drink alcohol, talk with your doctor about how much, if any, is safe for you to consume during treatment with Janumet or Janumet XR.

* Janumet and Janumet XR have a boxed warning Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source for this side effect. A boxed warning alerts doctors and patients about drug effects that may be dangerous. For more information about this side effect, see the “Janumet: Precautions” section below.

Janumet may interact with other medications.

Different interactions can cause different effects. Some interactions can interfere with a drug’s effectiveness. Others can increase a drug’s side effects or cause them to be severe.

Before you start Janumet, be sure to tell your doctor about any medications, herbs, vitamins, or supplements you take. They can check for any possible interactions between these products and Janumet or Janumet XR.

If any of the interactions listed below might pertain to you, talk with your doctor. They can tell you what you need to do to avoid the interaction.

• Janumet and certain medications. The manufacturer of Janumet and Janumet XR advises doctors to consider the risks and benefits of taking these drugs in combination. Be sure to discuss this with your doctor if these drugs have been prescribed together for you.
  • the angina drug ranolazine (Ranexa)
  • the thyroid cancer drug vandetanib (Caprelsa)
  • the HIV drug dolutegravir (Tivicay) and treatments that contain it, such as abacavir/dolutegravir/lamivudine (Triumeq) and dolutegravir/rilpivirine (Juluca)
  • the heartburn drug cimetidine (Tagamet HB)
• Janumet and certain other medications. Because Janumet or Janumet XR may interact with the following drugs, your doctor may monitor you more closely for side effects if you take it with these drugs. Examples include:
  • diuretic drugs, such as acetazolamide and hydrochlorothiazide
  • the paralysis drug dichlorphenamide (Keveyis)
  • insulin drugs, such as insulin glargine (Basaglar)
  • sulfonylureas, such as glipizide (Glucotrol XL)
  • birth control pills, such as drospirenone/ethinyl estradiol (Nikki, others)
  • corticosteroids, such as prednisone (Rayos)
  • certain antiseizure drugs, including phenytoin (Dilantin), topiramate (Topamax, others), and zonisamide (Zonegran)
  • the heart rhythm drugs verapamil (Verelan, others) and diltiazem (Cardizem, others)
• Janumet and herbs and supplements. Janumet and Janumet XR aren’t known to interact with any herbs or supplements.
• Janumet and foods. Janumet and Janumet XR aren’t known to interact with any foods.

For information about drug-condition interactions, see the “Janumet: Precautions” section below.

Your doctor will recommend how you should take Janumet or Janumet XR. It’s important to take the drug exactly as your doctor instructs.

Janumet and Janumet XR come as oral tablets. You’ll take the tablets by swallowing them.

Here’s a list of common questions related to taking Janumet or Janumet XR.

• When should I take Janumet or Janumet XR? Take Janumet or Janumet XR as instructed by your doctor. Janumet is typically taken twice per day. Janumet XR is typically taken once per day. Try these medication reminder options to help avoid missing doses of Janumet or Janumet XR. You could also set an alarm, use a timer, or download a reminder app on your phone.
• Do I need to take Janumet or Janumet XR with food? Yes, both Janumet and Janumet XR should be taken with food.
• Can Janumet or Janumet XR be chewed, split, or crushed? No, neither Janumet nor Janumet XR should be chewed, split, or crushed. Talk with your pharmacist or doctor if you’re having difficulty swallowing this medication.
• Is there a best time of day to take Janumet or Janumet XR? There’s no best time of day to take Janumet or Janumet XR. You should take doses according to your doctor’s instructions. Janumet is typically taken twice per day. You should try to space your doses apart if you’re prescribed Janumet. For example, you could take one dose with breakfast and one dose with dinner.

Janumet and Janumet XR are approved to help manage blood sugar levels in adults with type 2 diabetes. They’re prescribed for this use in combination with changes in diet and exercise.

With type 2 diabetes, your body develops insulin resistance. This is a condition in which your cells stop responding effectively to insulin.

Insulin is a hormone made by the body. It helps your cells take up sugar from the blood to use as energy or store for later. Insulin resistance prevents your cells from using sugar as effectively. In serious cases, your body can’t use insulin at all.

Insulin resistance causes your blood sugar levels to increase. Over time, untreated high blood sugar can lead to complications of diabetes.

Janumet and Janumet XR contain two active ingredients that work together to manage blood sugar levels. These active ingredients are sitagliptin and metformin.

The table below gives an overview of how each ingredient works to help manage insulin and blood sugar levels. (Keep in mind that insulin helps regulate blood sugar.)

Janumet and Janumet XR begin working soon after you take your first dose of either drug. These drugs are prescribed to help manage blood sugar levels. However, you won’t notice a change in your blood sugar right away.

In clinical studies of Janumet and Janumet XR, some people saw improvement in their conditions after 6 weeks of treatment. They were able to see this improvement through certain lab tests. However, it may take up to 24 weeks before the drug’s full effects are seen.

Your doctor can tell you more about how they’ll monitor how well Janumet or Janumet XR is working to treat your condition.

It isn’t known whether it’s safe to use Janumet or Janumet XR while pregnant.

Clinical studies have shown that managing blood sugar levels during pregnancy can lower the risk of certain complications. (Keep in mind that Janumet and Janumet XR are used to manage blood sugar in people with type 2 diabetes.) These complications include preeclampsia (high blood pressure during pregnancy) and pregnancy loss.

If you are pregnant or planning to become pregnant, talk with your doctor about treatment options for your diabetes. They can discuss the risks and benefits of various medications, including Janumet and Janumet XR.

Doctors aren’t sure whether it’s safe to take Janumet or Janumet XR during pregnancy. Talk with your doctor about your birth control needs with these drugs if you’re sexually active and you or your partner can become pregnant. Your doctor can recommend if you should use birth control with this medication.

It’s not known whether it’s safe to take Janumet or Janumet XR while breastfeeding. There haven’t been studies to see whether the drug passes into breast milk. So, it’s not clear whether it may cause side effects in a child who’s breastfed.

Your doctor can tell you more about the risks and benefits of different treatment options while you’re breastfeeding. These may include Janumet and Janumet XR. Your doctor can also discuss safe feeding options for your child.

This drug comes with several precautions.

This drug has a boxed warning Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source , the most serious warning from the Food and Drug Administration (FDA). A boxed warning alerts doctors and patients about drug effects that may be dangerous.

Risk of lactic acidosis. Lactic acidosis is a possible serious side effect of Janumet and Janumet XR. There have been reports of this condition with metformin, an ingredient in both versions of the drug. Lactic acidosis wasn’t reported in clinical studies of Janumet and Janumet XR. However, it has been reported since this drug was approved for use.

With lactic acidosis, lactic acid builds up in the blood. This side effect is rare. However, it can be life threatening, especially if not treated quickly.

Symptoms of lactic acidosis can include:

• abdominal pain
• sleepiness
• muscle pain
• difficulty breathing
• low blood pressure
• irregular heart rhythm

If you have symptoms of lactic acidosis, stop taking Janumet or Janumet XR and immediately call your doctor. However, if your symptoms seem life threatening, call 911 or a local emergency number. Or go to the closest emergency room.

Certain people may have a higher risk of lactic acidosis if they take Janumet or Janumet XR. These include people who:

• have kidney problems
• have liver problems
• use certain other medications
• are age 65 years or older
• have heart failure
• drink excessive amounts of alcohol
• have restricted food or fluid intake, such as before a surgery

Be sure to let your doctor know if you need to have surgery while you’re taking Janumet or Janumet XR. They may temporarily have you stop taking the medication until after your surgery.

Tell your doctor about your health history before starting treatment with Janumet or Janumet XR. Your doctor may not recommend this medication if you have certain factors affecting your health or specific medical conditions. These situations are considered drug-condition interactions.

These factors and conditions include those listed below.

• Older age. People age 65 years and older may be at a higher risk of lactic acidosis if they take Janumet or Janumet XR. For more information, see the “FDA warning: Risk of lactic acidosis” section directly above.
• Heart problems, including heart failure. Janumet and Janumet XR may cause new or worsened heart failure as a side effect. You may be at higher risk of heart failure with either drug if you have an existing heart problem. And if you have heart failure with Janumet or Janumet XR, you may also have a higher risk of lactic acidosis. For more information about this risk, see the “FDA warning: Risk of lactic acidosis” section directly above. Your doctor can provide more information about whether Janumet or Janumet XR is safe for you to take.
• Kidney or liver problems. Having kidney or liver problems may raise your risk of lactic acidosis with Janumet or Janumet XR. For more information, see the “FDA warning: Risk of lactic acidosis” section directly above.
• Low vitamin B12 level. Taking Janumet or Janumet XR may cause low vitamin B12 level as a side effect. If you already have a low vitamin B12 level, either medication could worsen your condition. There are treatments for low vitamin B12 levels that you can take while using Janumet or Janumet XR. Your doctor can discuss these treatments in more detail with you. They may also monitor your vitamin B12 levels closely while you’re taking Janumet or Janumet XR.
• Allergic reaction. Your doctor will likely not prescribe Janumet if you’ve had an allergic reaction to it or any of its ingredients. To find out about other treatment options, talk with your doctor.
• Pregnancy. If you’d like information about taking Janumet or Janumet XR while pregnant, view the “Janumet: Taking while pregnant” section above.
• Breastfeeding. If you’d like information about taking Janumet or Janumet XR while breastfeeding, view the “Janumet: Taking while breastfeeding” section above.

To learn more about effects of Janumet that could be harmful, see the “Janumet: Side effects” section above.

Serious effects can occur if you use more than the recommended dosage of Janumet. Do not use more Janumet than your doctor recommends.  

Symptoms that an overdose could cause include:

• low blood sugar level
• lactic acidosis (a dangerous buildup of lactic acid in your blood)*

* Janumet and Janumet XR have a boxed warning Trusted Source PubMed Central Highly respected database from the National Institutes of Health Go to source for this side effect. A boxed warning alerts doctors and patients about drug effects that may be dangerous. For more information about this side effect, see the “Janumet: Precautions” section below.

Call your doctor if you think you’ve taken too much of this drug. Also, you can call the American Association of Poison Control Centers at 800-222-1222 or use its online tool. However, if your symptoms are severe, call 911 or a local emergency number. Or go to the nearest emergency room right away.

Here’s some information about Janumet and Janumet XR’s expiration date, as well as how to store and dispose of the drug.

Expiration. Your pharmacist will add an expiration date to the label on Janumet or Janumet XR’s bottle or packaging. This date is usually 1 year from the date the medication was dispensed to you. Expiration dates help ensure that a medication is effective during a period of time.

The Food and Drug Administration (FDA) advises Trusted Source Food and Drug Administration (FDA) Governmental authority Go to source that you avoid taking expired drugs. If you have an unused medication and it’s past the drug’s expiration date, talk with your pharmacist. They can let you know whether you might still be able to use the medication.

Storage. Many factors determine how long a medication remains good to use. These factors include how and where you store the drug. Janumet and Janumet XR tablets should be stored at room temperature from 68°F to 77°F (20°C to 25°C). Avoid storing it in areas where it could get damp or wet, such as bathrooms.

Disposal. It’s important to safely dispose of Janumet if you no longer need to take it and have unused medication. Doing so helps prevent others, including children and pets, from accidentally taking the drug. It also helps avoid causing harm to the environment.

Ask your pharmacist for information about disposing of Janumet. Also, check out this page for several tips on safe medication disposal.

If you have questions about Janumet, talk with your doctor. They can help advise you on whether Janumet could be a good treatment option for you.

Here’s a list of questions you may want to ask your doctor:

• Will Janumet or Janumet XR interact with any of my other medications?
• What happens if my insurance coverage changes while I’m taking Janumet or Janumet XR?
• How will we monitor whether Janumet or Janumet XR is working for me?
• What determines whether Janumet or Janumet XR is a better choice for me?

Your doctor may also tell you about other treatment options for your condition. You may find this article helpful in learning about alternative drugs. And view our selection of videos on diabetes.

Disclaimer: Healthgrades has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.