Drug Detail:Januvia (Sitagliptin [ si-ta-glip-tin ])
Drug Class: Dipeptidyl peptidase 4 inhibitors
1. How it works
- Januvia is a brand (trade) name for sitagliptin.
- Januvia (sitagliptin) may be used to treat type 2 diabetes and is thought to work by increasing insulin release and decreasing glucagon levels by slowing the inactivation of incretin hormones. Incretin hormones are released by the intestine throughout the day and in response to food. These hormones are rapidly inactivated by an enzyme called dipeptidyl peptidase 4 (DPP-4).
- Januvia belongs to the class of medicines known as DPP-4 inhibitors. It is selective for DPP-4 and does not inhibit DDP-8 or DPP-9 (the inhibition of these two enzymes has been associated with severe toxicity).
2. Upsides
- Used in addition to diet and exercise to improve blood glucose control in people with type 2 diabetes.
- In people with type 2 diabetes, Januvia significantly improved hemoglobin A1C, fasting plasma glucose, and 2-hour postprandial glucose.
- Research has shown that controlling high blood sugar helps to prevent kidney, eye, and nerve damage, lessen the risk of heart attack and stroke, and help reduce sexual dysfunction in people with diabetes.
- May be taken with or without food.
- May be used in combination with other medicines for type 2 diabetes.
- Does not cause drowsiness.
- Januvia is an oral tablet that is taken once a day.
3. Downsides
If you are between the ages of 18 and 60, take no other medication or have no other medical conditions, side effects you are more likely to experience include:
- Nasopharyngitis (stuffy, runny nose, or a sore throat), upper respiratory tract infections, diarrhea, and a headache are the most common side effects.
- Not effective for the treatment of type 1 diabetes or for diabetic ketoacidosis.
- Januvia has been associated with pancreatitis (inflammation of the pancreas). Symptoms include persistent abdominal pain and vomiting. People with a history of pancreatitis, gallstones, high triglyceride levels, kidney disease, or who drink alcohol excessively are more at risk.
- Severe and disabling joint pain has also been reported in people taking DPP-4 inhibitors. May occur on drug initiation or years later.
- May not be suitable for some people including those with kidney disease, heart disease, gallstones, high blood triglyceride levels, or a history of excessive alcohol use or pancreatitis. Use of Januvia may precipitate heart failure in those at higher risk for heart failure.
- The dosage of Januvia requires adjusting in moderate and severe renal disease.
- The dosage of other antidiabetic medications (such as sulfonylureas or insulin) may need adjusting to reduce the risk of hypoglycemia. Januvia may also increase peak digoxin levels if they are taken together. Monitor for digoxin toxicity.
- Rarely, serious hypersensitivity reactions have been reported with Januvia, including anaphylaxis, angioedema, and Stevens-Johnson syndrome.
- Occasionally, other skin reactions, including bullous pemphigoid have been reported.
- Not recommended for children under the age of 18 years.
- Only available as a tablet.
- There is currently no generic version of Januvia.
Note: In general, seniors or children, people with certain medical conditions (such as liver or kidney problems, heart disease, diabetes, seizures) or people who take other medications are more at risk of developing a wider range of side effects. View complete list of side effects
4. Tips
- Take exactly as directed by your doctor. Do not take more or less than intended. The usual dosage of Januvia is 100mg once daily.
- May be taken with or without food.
- Discontinue Januvia and seek urgent medical advice if unexplained joint pain, skin rash, persistent abdominal pain, unexplained vomiting, or other allergy-type symptoms develop.
- Januvia does not take the place of good adherence to dietary recommendations and regular physical activity.
- Regularly monitor your blood glucose levels as recommended by your doctor. Seek further medical advice during times of illness or stress or prior to surgery.
- Keep some fruit juice, hard candy (such as lifesavers), or another source of sugar with you at all times in case you have low blood sugar. Symptoms of low blood sugar include a headache, sweating, irritability, difficulty concentrating, and feeling shaky. Show your friends and family how to administer glucagon in an emergency situation if your blood sugars have gone too low and you are unconscious.
- Talk to a doctor or pharmacist before taking any other medication with Januvia, including that bought over-the-counter, to check that it is compatible with Januvia.
5. Response and effectiveness
Januvia is rapidly absorbed with peak plasma concentrations occurring one to four hours after a dose. Administration of one dose of Januvia leads to inhibition of DPP-4 activity for 24 hours.
6. Interactions
Medicines that interact with Januvia may either decrease its effect, affect how long it works for, increase side effects, or have less of an effect when taken with Januvia. An interaction between two medications does not always mean that you must stop taking one of the medications; however, sometimes it does. Speak to your doctor about how drug interactions should be managed.
Common medications that may interact with Januvia include:
- digoxin
- other medications for diabetes, such as insulin, chlorpropamide, glimepiride, glipizide, glyburide, tolazamide, or tolbutamide.
Alcohol may affect your blood sugar levels. Do not drink alcohol while taking Januvia without talking to your doctor first.
Note that this list is not all-inclusive and includes only common medications that may interact with Januvia. You should refer to the prescribing information for Januvia for a complete list of interactions.