sitagliptin (Januvia)

Sitagliptin is an oral drug that reduces blood sugar (glucose) levels in patients with type 2 diabetes. Sitagliptin is indicated as an adjunct to diet and exercise.

Sitagliptin should not be used in patients with type 1 diabetes or for the treatment of diabetic ketoacidosis, as it would not be effective in these settings.

Sitagliptin is a member of a class of drugs that inhibit the enzyme, dipeptidyl peptidase-4 (DPP-4) and are therefore called DPP-4 inhibitors. Other members of the class include saxagliptin (Onglyza) and linagliptin (Tradjenta) Following a meal, incretin hormones such as glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) are released from the intestine, and their levels increase in the blood. GLP-1 and GIP reduce blood glucose by increasing the production and release of insulin from the pancreas. GLP-1 also reduces blood glucose by reducing the secretion by the pancreas of the hormone, glucagon, a hormone that increases the production of glucose by the liver and raises the blood level of glucose. The net effect of increased release of GLP-1 and GIP is to reduce blood glucose levels. Sitagliptin inhibits the enzyme, DPP-4, that destroys GLP-1 and GIP and thereby increases the levels and activity of both hormones. As a result, blood glucose levels fall. In summary, sitagliptin reduces blood glucose levels by inhibiting DPP-4 and increasing the levels of GLP-1 and GIP. Sitagliptin was approved by the FDA in October 2006.

What brand names are available for sitagliptin?

Januvia

Is sitagliptin available as a generic drug?

No

Do I need a prescription for sitagliptin?

Yes

WARNING

• There have been postmarketing reports of acute pancreatitis, including fatal and non-fatal hemorrhagic or necrotizing pancreatitis. If pancreatitis is suspected, promptly discontinue sitagliptin.
• There have been postmarketing reports of acute renal failure, sometimes requiring dialysis. Dosage adjustment is recommended in patients with moderate or severe renal insufficiency and in patients with ESRD. Assessment of renal function is recommended prior to initiating sitagliptin and periodically thereafter.
• There is an increased risk of hypoglycemia when sitagliptin is added to an insulin secretagogue (e.g., sulfonylurea) or insulin therapy. Consider lowering the dose of the sulfonylurea or insulin to reduce the risk of hypoglycemia.
• There have been postmarketing reports of serious allergic and hypersensitivity reactions in patients treated with sitagliptin such as anaphylaxis, angioedema, and exfoliative skin conditions including Stevens-Johnson syndrome. In such cases, promptly stop sitagliptin, assess for other potential causes, institute appropriate monitoring and treatment, and initiate alternative treatment for diabetes.
• There have been no clinical studies establishing conclusive evidence of macrovascular risk reduction with sitagliptin or any other anti-diabetic drug.

Common side effects

The most common side effects of sitagliptin are:

• upper respiratory tract infection and
• headache.

Other important side effects of sitagliptin include:

• abdominal pain,
• nausea and
• diarrhea.

Sitagliptin may be taken with or without food. The recommended dose is 100 mg once daily. Renal function should be assessed prior to starting sitagliptin and periodically during treatment. The dose of sitagliptin should be modified based on renal function.

Sitagliptin may slightly increase the concentration of digoxin (Lanoxin) in the body when both drugs are being taken. Digoxin concentrations should be monitored appropriately. The occurrence of low blood glucose increases when sitagliptin is combined with a sulfonylurea (for example, glyburide [Micronase, Diabeta, Glynase, Prestab]) or insulin. The dose of insulin or sulfonylurea should be reduced.

There are no adequate studies of sitagliptin in pregnant women.

It is unknown whether sitagliptin is secreted in human breast milk.

What preparations of sitagliptin are available?

Tablets: 25, 50, and 100 mg

How should I keep sitagliptin stored?

Tablets should be stored at room temperature, 15-30 C (59-86 F)