If you have type 2 diabetes, your doctor might prescribe Januvia.

It’s used together with diet and exercise to help manage blood sugar levels in adults with type 2 diabetes. With this condition, your blood sugar levels are too high.

If you have type 1 diabetes or you’ve ever had pancreatitis (inflammation of the pancreas), Januvia may not be right for you.

To learn more about Januvia and how it’s used, see the “What is Januvia used for?” section below.

Januvia basics

Januvia contains the active drug sitagliptin. It comes as tablets that you’ll take by mouth.

Januvia is a brand-name drug. There isn’t a generic form.

Read on to learn more about Januvia’s side effects, dosages, uses, and more.

Like most drugs, Januvia may cause mild or serious side effects. The lists below describe some of the more common side effects it may cause. These lists don’t include all possible side effects.

Keep in mind that side effects of a drug can depend on:

  • your age
  • other health conditions you have
  • other medications you may be taking

Your doctor or pharmacist can tell you more about the potential side effects of Januvia. They can also suggest ways to help reduce side effects.

Mild side effects

Here’s a short list of some of the mild side effects that Januvia can cause. To learn about other mild side effects, talk with your doctor or pharmacist, or read Januvia’s medication guide.

Mild side effects of Januvia that have been reported include:

Mild side effects of many drugs may go away within a few days or a couple of weeks. But if they become bothersome, talk with your doctor or pharmacist.

* This side effect was reported when Januvia was used with certain other diabetes medications.

Serious side effects

Serious side effects from Januvia can occur, but they aren’t common. If you have serious side effects from this drug, call your doctor right away. However, if you think you’re having a medical emergency, you should call 911 or your local emergency number.

Serious side effects of Januvia that have been reported include:

* For more information about this side effect, see the “Side effect focus” section below.

Side effect focus

Learn more about some of the side effects Januvia may cause.

Pancreatitis

Januvia can cause severe inflammation of the pancreas, which is also called pancreatitis.

With pancreatitis you may have belly pain that spreads to your back. And it’s usually a sharp pain. Pancreatitis can also cause nausea and vomiting.

What might help

Tell your doctor right away if you have symptoms of pancreatitis while you’re taking Januvia.

If you have pancreatitis, your doctor may have you stop taking Januvia. But do not stop taking the drug without first talking with your doctor.

To treat pancreatitis, your doctor will give you fluids through an intravenous (IV) injection. An IV injection is given directly into your veins.

Hypoglycemia

You may have hypoglycemia (low blood sugar level) with Januvia.

If you’re taking Januvia with insulin or drugs that cause your pancreas to release insulin, your risk of having hypoglycemia is high. (Insulin helps lower your blood sugar levels.) Diabetes drugs that cause insulin to be released include sulfonylurea drugs. Examples include glyburide (Glynase) and glimepiride (Amaryl).

Symptoms of hypoglycemia may include:

If you have any of these symptoms, check your blood sugar level to see if it’s low.

What might help

If you’re taking insulin or drugs that cause its release together with Januvia, your doctor may lower your dosage of them. Do not lower the dosage of any medications or change how you take them without talking with your doctor.

To help prevent low blood sugar levels with Januvia, you’ll want to check your blood sugar level. Your doctor will tell you how often to do this. How often you’ll need to check depends on several factors. These include other diabetes drugs you’re taking and whether you’ve had low blood sugar levels in the past.

If you have hypoglycemia, you can safely increase your blood sugar level by eating something that contains sugar. The 15-15 rule can help get your blood sugar level to a level that’s in the preferred range. To follow this rule, you’ll eat 15 grams (g) of sugar, wait 15 minutes, then recheck your blood sugar. If your blood sugar is still too low, you’ll consume another 15 g of sugar.

Foods that give you 15 g of sugar include:

  • 4 ounces (half a cup) of juice or regular (non-diet) soda
  • 1 tablespoon of sugar, honey, or corn syrup
  • hard candies, jellybeans, or gumdrops
  • glucose tablets

Ask your doctor or pharmacist about the best way to increase your blood sugar to a safe level. Make sure you have sources of sugar available so you can quickly treat hypoglycemia if you have it.

Joint pain

Some people have severe and disabling joint pain with Januvia. Joint pain can start after the first dose of Januvia or after several years of treatment.

Drugs in the same group of medications as Januvia can also cause joint pain. These other drugs include saxagliptin (Onglyza) and linagliptin (Tradjenta).

What might help

If you have joint pain after starting Januvia, talk with your doctor right away. This can be a serious side effect.

Your doctor may have you stop taking Januvia if you have severe and disabling joint pain.

Once you stop the drug, your joint pain may go away. But do not stop taking Januvia without first talking with your doctor.

If you restart Januvia or take a drug from the same group of medications, your joint pain may come back.

Allergic reaction

Some people may have an allergic reaction to Januvia.

Symptoms of a mild allergic reaction can include:

  • skin rash
  • itchiness
  • flushing (temporary warmth, redness, or deepening of skin color)
  • hives

A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include swelling under your skin, typically in your face, eyelids, lips, hands, or feet. They can also include swelling of your tongue, mouth, or throat, which can cause trouble breathing.

Call your doctor right away if you have an allergic reaction to Januvia. But if you think you’re having a medical emergency, call 911 or your local emergency number.

Your doctor will recommend the dosage of Januvia that’s right for you. Below are commonly used dosages, but always take the dosage your doctor prescribes.

Form and strengths

Januvia comes as tablets that you’ll take by mouth.

It’s available in strengths of:

  • 100 milligrams (mg)
  • 50 mg
  • 25 mg

Recommended dosage

You’ll take Januvia once each day. Your doctor will tell you how much Januvia to take. They’ll let you know the drug’s recommended daily dose and its maximum dose.

If you have kidney problems, you might need renal dosing of Januvia. Renal dosing is typically a lower dose than usual.

Questions about Januvia’s dosage

Here’s a list of common questions related to Januvia’s dosage.

  • What if I miss a dose of Januvia? If you miss a dose of Januvia, take it as soon as you remember. But if it’s close to your next usual dose of Januvia, skip the missed dose and take your next scheduled dose. If you’re not sure when you should take your next dose of Januvia, ask your doctor or pharmacist.
  • Will I need to use Januvia long term? Type 2 diabetes, which Januvia treats, is a long-lasting condition. And it cannot be cured. So you’ll likely need to take Januvia long term. Talk with your doctor to find out how long you should take this drug. Depending on how your condition progresses over time, your doctor may adjust your dosage or recommend other diabetes medications.
  • How long does Januvia take to work? Januvia acts quickly to block a certain protein in your body. But you might not notice a difference in your blood sugar levels until several months have passed. In studies, some people had improvements in their blood sugar levels after 18 weeks of treatment.

If you have type 2 diabetes, your doctor might prescribe Januvia. It’s used together with diet and exercise to help manage blood sugar levels in adults with this condition.

With type 2 diabetes, your blood sugar levels are too high. This is because the insulin that your body naturally releases doesn’t work as well as usual. (Your body uses insulin to lower your blood sugar level.)

Januvia blocks a certain protein in your body that inactivates incretin hormones. These hormones help control your blood sugar levels by affecting your pancreas and stimulating it to make and release insulin. By blocking the protein, more active incretin hormones are available to help control your blood sugar levels.

Note: Januvia’s indication doesn’t include type 1 diabetes. In fact, this is a limitation of the drug, which means it cannot be used for the condition. Additionally, Januvia isn’t used to treat diabetes in people who have had pancreatitis (inflammation of the pancreas). It’s not known if Januvia is safe in people who have had pancreatitis. This is another limitation to Januvia’s uses. (See the “What are Januvia’s side effects?” section above for more information about pancreatitis.)

Find answers below to some commonly asked questions about Januvia.

Is Januvia similar to alternatives, such as Jardiance, Trulicity, or glipizide?

Jardiance, Trulicity, and glipizide are all used for diabetes. Each of these drugs belongs to a different group of medications, and they work differently than Januvia.

Certain diabetes drugs have benefits besides managing blood sugar levels in people with diabetes. For example, certain drugs can help reduce the risk of heart disease in people with diabetes. But Januvia isn’t one of these drugs. Examples of diabetes drugs that reduce the risk of heart disease include:

Like Januvia, glipizide is a diabetes drug that stimulates the pancreas to release insulin. (Insulin helps lower blood sugar levels.) It belongs to the same group of diabetes drugs as glyburide (Glynase) and glimepiride (Amaryl).

Unlike Januvia, which comes as tablets, Victoza and Trulicity come as injections. But similar to Januvia, they’re used to treat diabetes.

All the drugs mentioned here treat type 2 diabetes, but they don’t treat type 1 diabetes.

Sometimes your doctor may prescribe Januvia together with metformin. Depending on the dose of each drug you’re taking, you may be able to take Janumet. This medication contains both sitagliptin (the active drug in Januvia) and metformin.

To know which diabetes drug is best for you, talk with your doctor.

How does Januvia work?

Januvia is a dipeptidyl peptidase-4 (DPP-4) blocker.

DPP-4 is a protein that blocks the action of incretin hormones. Incretins help control your body’s blood sugar levels. When you eat a meal, your digestive tract releases incretins. They affect your pancreas, stimulating it to make and release insulin. And insulin lowers your blood sugar levels.

By blocking DPP-4, more incretin hormones are available to help control your blood sugar level. This is Januvia’s mechanism of action.

Is Januvia used for weight loss?

Januvia isn’t prescribed for weight loss. Instead, it’s prescribed together with diet and exercise for type 2 diabetes.

Like Januvia, diet and exercise can help control your blood sugar levels.

Type 2 diabetes typically occurs in adults who have high blood sugar levels because of certain lifestyle and nutrition factors. Having healthy diet and exercise habits while taking Januvia may help you manage your weight. So you may notice changes in your weight during treatment.

Does Januvia cause cancer, such as pancreatic cancer?

It’s not known if Januvia causes cancer.

One study found that higher doses of Januvia were related to a higher risk of pancreatic cancer. Researchers suggest keeping Januvia doses at less than 100 milligrams (mg). But more evidence is needed to confirm this recommendation.

Another study suggested that certain people may have a higher risk of thyroid cancer with Januvia. But more evidence is needed to support this, too.

According to another study, Januvia may reduce the risk of breast cancer in people with diabetes. But these findings require more study as well.

If you have concerns about your risk of cancer with Januvia, talk with your doctor or pharmacist.

Will I have weight gain, hair loss, or erectile dysfunction with Januvia?

No, these aren’t side effects of Januvia.

This drug doesn’t affect your weight. But Januvia is meant to be used together with healthy diet and exercise habits. And these measures may lead to weight changes.

Hair loss isn’t a reported side effect of Januvia. But it can be an early sign of type 2 diabetes, which Januvia is used to treat. More studies are needed to confirm the effects of blood sugar levels on hair loss.

Erectile dysfunction hasn’t been reported as a side effect of Januvia. But this condition can occur with diabetes that’s not well managed.

If you’re concerned about these conditions, talk with your doctor or pharmacist.

Does Januvia treat type 1 diabetes?

No, Januvia does not treat type 1 diabetes. In fact, this is one of the drug’s limitations of use, which means it cannot be used for the condition.

Instead, Januvia is prescribed for people with type 2 diabetes. To learn more about this condition, see the “What is Januvia used for?” section above.

With type 1 diabetes, your body doesn’t make or release enough insulin. (Insulin is used to help lower your blood sugar levels.) With this condition, your immune system destroys the cells in your pancreas that make and release insulin. So, treatment for type 1 diabetes requires insulin therapy. But Januvia isn’t an insulin drug.

Costs of prescription drugs can vary depending on many factors. These factors include what your insurance plan covers and which pharmacy you use. To find current prices for Januvia tablets in your area, visit GoodRx.com. The drug’s cost with insurance may differ, though.

Januvia isn’t available as a generic drug. Generics usually cost less than brand-name drugs.

If you have questions about how to pay for your prescription, talk with your doctor or pharmacist. You can also visit the Januvia manufacturer’s website to see if they have support options.

Your doctor will explain how you should take Januvia. They’ll also explain how much to take and how often. Be sure to follow your doctor’s instructions.

Taking Januvia

Januvia comes as tablets that you’ll take by mouth.

Taking Januvia with other drugs

Januvia is used to treat type 2 diabetes. This condition sometimes requires many different medications for treatment.

Different types of diabetes medications can help manage blood sugar levels in people with diabetes. Your doctor will recommend which drugs you’ll need to take for your blood sugar levels.

Examples of drugs that your doctor may prescribe with Januvia include:

Questions about taking Januvia

Here’s a list of questions related to taking Januvia.

  • Can Januvia be chewed, crushed, or split? No, you should not chew, crush, or split Januvia tablets. Instead, you must swallow them whole. If you’re having trouble swallowing Januvia tablets whole, talk with your doctor or pharmacist.
  • Should I take Januvia with food? You can take Januvia with or without food. But taking the drug with or without food may affect how much of it your body absorbs. To help keep your levels of Januvia consistent, take it the same way every day.
Questions for your doctor

You may have questions about Januvia and your treatment plan. It’s important to discuss all your concerns with your doctor.

Here are a few tips that might help guide your discussion:

  • Before your appointment, write down questions such as:
    • How will Januvia affect my body, mood, or lifestyle?
  • Bring someone with you to your appointment if doing so will help you feel more comfortable.
  • If you don’t understand something related to your condition or treatment, ask your doctor to explain it to you.

Remember, your doctor and other healthcare professionals are available to help you. And they want you to get the best care possible. So, don’t be afraid to ask questions or offer feedback on your treatment.

Januvia contains the active drug sitagliptin, and Tradjenta contains the active drug linagliptin.

These medications belong to the same group of diabetes medications. And they act in the same way to manage type 2 diabetes.

To learn about how Januvia and Tradjenta compare, see this article. Also, be sure to ask your doctor which medication is right for you.

Metformin is an active drug ingredient. It comes as a generic drug. Januvia is a brand-name drug that contains the ingredient sitagliptin.

Metformin is one of the most commonly prescribed drugs for type 2 diabetes. But it works differently than Januvia.

Sometimes, doctors prescribe both metformin and Januvia to manage diabetes. Depending on the prescribed doses of each drug, a doctor might prescribe the combination drug called Janumet. Janumet contains both metformin and sitagliptin.

If you’d like to learn about the similarities and differences between Januvia and metformin, see this article. Talk with your doctor to see which drug is better for you.

Some important things to discuss with your doctor when considering Januvia include your overall health and any conditions you have.

Also, tell your doctor if you’re taking any medications. This is important because some medications can interfere with Januvia.

These and other considerations are described below.

Interactions

Taking a medication with certain vaccines, foods, and other things can affect how the medication works. These effects are called interactions.

Before taking Januvia, be sure to tell your doctor about all medications you take, including prescription and over-the-counter types. Also describe any vitamins, herbs, or supplements you use. Your doctor or pharmacist can tell you about any interactions these items may cause with Januvia.

Interactions with drugs or supplements

Januvia can interact with several types of drugs, including:

This list does not contain all types of drugs that may interact with Januvia. Your doctor or pharmacist can tell you more about these interactions and any others that may occur with use of Januvia.

Warnings

Januvia may not be right for you if you have certain medical conditions or other factors that affect your health. Talk with your doctor about your health history before you take Januvia. Factors to consider include those in the list below.

  • Heart failure. If you have problems with your heart, Januvia may not be right for you. Januvia can cause or worsen heart failure. Before prescribing Januvia, your doctor will tell you if the benefits of taking it outweigh its possible risks. While taking Januvia, your doctor will check you for heart failure. Symptoms may include swelling of your feet, ankles, or legs, changes in your weight, and trouble breathing.
  • Kidney problems. Some people may have kidney side effects, such as kidney failure, while taking Januvia. If Januvia affects your kidneys, you might need dialysis therapy. (Dialysis is a type of treatment used to remove waste from your blood when your kidneys aren’t working well.) Before you start taking Januvia, your doctor will check to see how well your kidneys are working. If your kidneys aren’t working well, your doctor may adjust your Januvia dosage. Do not stop taking Januvia or change your dosage without first talking with your doctor. If you think you have kidney side effects from Januvia, call your doctor. Symptoms of kidney problems may include diarrhea, nausea, and vomiting.
  • Allergic reaction. If you’ve had an allergic reaction to Januvia or any of its ingredients, you should not take Januvia. Ask your doctor what other medications are better options for you.

Januvia and alcohol

Some medications interact with alcohol, but Januvia isn’t one of them. However, before starting Januvia, ask your doctor or pharmacist if it’s safe for you to drink alcohol.

Keep in mind, Januvia is used to help manage blood sugar levels in people with diabetes. Studies show that alcohol can impact blood sugar levels because it affects insulin. (Insulin helps lower your blood sugar levels.)

Drinking alcohol can increase or decrease insulin’s effect. Depending on how much alcohol is consumed, it may have different effects on your blood sugar level.

Tell your doctor if you drink alcohol. And let them know how much you drink. Your doctor can recommend whether drinking is safe for your blood sugar levels.

Pregnancy and breastfeeding

It’s not known if Januvia is safe to take during pregnancy. But having diabetes that’s not well managed during pregnancy is unsafe for both a pregnant person and the fetus.

Before taking Januvia, tell your doctor if you’re pregnant or considering pregnancy. They can help you safely manage your diabetes during pregnancy.

If you do take Januvia during pregnancy, consider enrolling in the drug’s pregnancy registry. A pregnancy registry collects information on the effects of medication use during pregnancy. Reporting effects of Januvia during pregnancy helps researchers better understand the drug’s risks with pregnancy. To enroll in Januvia’s registry, call 800-986-8999.

It’s also unknown if Januvia passes into breast milk or if it affects how your body makes breast milk. If you’re breastfeeding or considering doing so, talk with your doctor before starting Januvia. Your doctor will help you weigh the risks and benefits of taking this drug.

Do not take more Januvia than your doctor prescribes. Using more than this can lead to serious side effects. If you take too much Januvia, your doctor may closely monitor you for overdose.

What to do in case you take too much Januvia

Call your doctor if you think you’ve taken too much Januvia. You can also call 800-222-1222 to reach the American Association of Poison Control Centers or use its online resource. However, if you have severe symptoms, immediately call 911 (or your local emergency number) or go to the nearest emergency room.

If you have type 2 diabetes, your doctor might prescribe Januvia.

If you have questions about taking this drug, talk with your doctor or pharmacist. They can tell you about other treatments you can use for your condition.

Here’s an article about diabetes treatments you might find helpful. And here are some questions you can ask your doctor about Januvia:

  • Can I take Januvia with natural diabetes remedies, such as apple cider vinegar?
  • How often do I need to check my blood sugar levels when taking Januvia?
  • Is Januvia better than other drugs, such as saxagliptin (Onglyza), linagliptin (Tradjenta), and alogliptin (Nesina)?
  • Can I reduce the number of pills I take for diabetes by switching to Janumet?
  • Does Januvia interact with birth control, such as birth control pills?
  • Will Januvia make me constipated?

You can learn more about diabetes, which Januvia is used for, by subscribing to Healthline’s type 2 diabetes newsletter.

Disclaimer: Healthline 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.