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Januvia

Generic name: sitagliptin

Last updated August 27, 2026 0 views Reviewed by Philip Thornton, DipPharm
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What is Januvia?

Januvia is an oral diabetes medicine that helps control blood sugar levels. It works by regulating the levels of insulin your body produces after eating.

Januvia is used together with diet and exercise to improve blood sugar control in adults with type 2 diabetes mellitus.

Januvia is not for treating type 1 diabetes.

How should I take Januvia?

Take Januvia exactly as it was prescribed for you. Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

You may take Januvia with or without food. Follow your doctor's instructions.

Your blood sugar may need to be checked often, and you may need other blood tests at your doctor's office.

You may have low blood sugar (hypoglycemia) and feel very hungry, dizzy, irritable, confused, anxious, or shaky. To quickly treat hypoglycemia, eat or drink a fast-acting source of sugar (fruit juice, hard candy, crackers, raisins, or non-diet soda).

Your doctor may prescribe a glucagon injection kit in case you have severe hypoglycemia. Be sure your family or 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.

Januvia is only part of a complete treatment program that may also include diet, exercise, weight control, blood sugar testing, and special medical care. Follow your doctor's instructions very closely.

Store the tablets at room temperature away from moisture, heat, and light. Keep the tablets in their original container and use within 6 months of opening.

Warnings

You should not use Januvia if you are in a state of diabetic ketoacidosis (call your doctor for treatment with insulin).

Call your doctor if you have symptoms of heart failure--shortness of breath (even while lying down), swelling in your legs or feet, rapid weight gain, or unusual tiredness.

Stop taking Januvia and call your doctor if you have symptoms of pancreatitis: severe pain in your upper stomach spreading to your back, with or without vomiting.

Before taking this medicine

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

Tell your doctor if you have ever had:

  • kidney disease (or if you are on dialysis);
  • heart problems;
  • pancreatitis;
  • high triglycerides (a type of fat in the blood);
  • gallstones; or
  • alcoholism.

Follow your doctor's instructions about using Januvia if you are pregnant or you become pregnant. Blood sugar control is very important during pregnancy, and your dose needs may be different during each trimester. Having high blood sugar may cause complications in both the mother and the baby.

Your name may need to be listed on a Januvia pregnancy registry when you start using this medicine.

It may not be safe to breast-feed a baby while you are using this medicine. Ask your doctor about any risks.

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

Januvia side effects

Get emergency medical help if you have signs of an allergic reaction to Januvia (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 Januvia and call your doctor right away if you have symptoms of pancreatitis: severe pain in your upper stomach spreading to your back, with or without vomiting.

Call your doctor at once if you have:

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

Common Januvia side effects may include:

  • low blood sugar;
  • headache; or
  • runny or stuffy nose, 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.

Dosing information

Usual Adult Dose for Diabetes Type 2:

Usual dose: 100 mg orally once a day Comments: When used in combination with an insulin secretagogue (e.g. sulfonylurea) or insulin, a lower dose of the insulin secretagogue or insulin may be required to reduce the risk of hypoglycemia. Use: As an adjunct to diet and exercise to improve glycemic control in patients with type 2 diabetes mellitus.

What happens if I miss a dose?

Take the medicine 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?

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).

Follow your doctor's instructions about any restrictions on food, beverages, or activity.

What other drugs will affect Januvia?

Januvia may not work as well when you use other medicines at the same time. Many other drugs can also affect blood sugar control.

You may be more likely to have low blood sugar if you also use insulin.

Other drugs may affect sitagliptin, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all your current medicines and any medicine you start or stop using.

This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here. Tell your doctor about all medicines you start or stop using.

Because of the prescription drug law, known as the Inflation Reduction Act, Medicare is able to negotiate directly with drug companies to improve access to some of the costliest single-source brand-name Medicare Part B and Part D drugs.

Januvia is one of 10 drugs covered under Medicare Part D that were selected in 2024 for the first cycle of negotiation based on Total Expenditures under Part D and other criteria as required by the law. Negotiations with participating drug companies are ongoing, and any negotiated prices for the first cycle of negotiation is effective from 2026.

Common questions about Januvia

When is the best time to take Januvia?
There is no single best time of day to take Januvia (generic name: sitagliptin). You can take it in the morning, at night, or any time in between, with or without food. What matters is picking one time and sticking to it. One dose keeps working for a full 24 hours, so consistency is what keeps your blood sugar steady. Continue reading
How long does it take for Januvia to work?
Januvia (sitagliptin) starts working within hours of your first dose, but you will not feel it. Most people see lower blood sugar readings within 1 to 2 weeks. Your A1C, which reflects about 3 months of blood sugar, usually shows a clear drop by 12 weeks. Full effects were measured at 24 weeks in clinical studies. Continue reading
Does Januvia cause weight gain or loss?
Januvia (sitagliptin) does not usually cause weight gain or weight loss. Doctors call it "weight neutral." In FDA-reviewed studies, people taking Januvia by itself did not gain weight, and most weight changes were under 2 pounds in either direction. When the scale does move, it is usually the other diabetes medicines taken alongside Januvia that explain the change. Continue reading
What is Januvia used for and how does it work?
Januvia (generic name: sitagliptin) is a prescription oral diabetes tablet taken once daily, along with diet and exercise, to help to lower blood sugar levels (glucose) in adults living with type 2 diabetes. Januvia works by adjusting the levels of insulin and glucose your body makes after eating. It is taken once a day and is used in addition to diet and exercise to improve your blood sugar control (measured by an A1C test). Continue reading
Can Victoza and Januvia be used together?
No. Victoza and Januvia are not recommended together. Victoza (liraglutide) and Januvia (sitagliptin) both work on the same hormone system in your body. The American Diabetes Association (ADA) 2026 Standards of Care say adding a DPP-4 inhibitor like Januvia to a GLP-1 drug like Victoza does not lower blood sugar any further than the GLP-1 drug alone. Taking both means paying for two drugs and getting the benefit of one. Continue reading
Can Januvia and Invokana be taken together?
Yes. Januvia (sitagliptin) and Invokana (canagliflozin) can be taken together, and doctors prescribe this pair often. The two drugs lower blood sugar in completely different ways, so pairing them gives you more A1C lowering than either drug alone. Continue reading

Related medicines

Before you take this medicine: the information on this page is general and may not cover your personal circumstances. Read the label supplied with your medicine and ask a pharmacist or doctor if you are unsure, especially if you are pregnant, breastfeeding, taking other medicines or managing a long-term condition.
General medicine information Consumer-friendly language Source: Drugs.com

Content is provided for education and is not medical advice. See our medical disclaimer. Source page medically reviewed by Philip Thornton, DipPharm on August 27, 2026.