sitagliptin phosphate

Action

Inhibits DPP-4 and slows inactivation of incretin hormones, helping to regulate glucose homeostasis through increased insulin release and decreased glucagon levels

Availability

Tablets: 25 mg, 50 mg, 100 mg

Indications and dosages

➣ Adjunct to diet and exercise to improve glycemic control in type 2 diabetes mellitus

Adults: 100 mg P.O. once daily

Dosage adjustment

• Moderate to severe renal insufficiency or end-stage renal disease

Contraindications

• History of serious hypersensitivity to drug (such as anaphylaxis or angioedema)

Precautions

Use cautiously in:

• concurrent administration of drugs that cause hypoglycemia (such as sulfonylureas or insulin)

• renal impairment, history of pancreatitis

• pregnant or breastfeeding patients

• children younger than age 18 (safety and efficacy not established).

Administration

• Assess renal function before starting therapy.

See Before starting drug, ask patient about possible risk factors for pancreatitis, such as history of pancreatitis, alcoholism, gallstones, or hypertriglyceridemia. However, it's unknown if these conditions make it more likely that pancreatitis will occur.

• Give with or without food.

• Be aware that drug shouldn't be used to treat type 1 diabetes mellitus or diabetic ketoacidosis.

• Know that when drug is used with a sulfonylurea, a lower dose of sulfonylurea may be required, to reduce risk of hypoglycemia.

Adverse reactions

CNS: headache

EENT: nasopharyngitis

GI: abdominal pain, nausea, vomiting, diarrhea, pancreatitis

GU: acute renal failure

Respiratory: upper respiratory tract infection

Other: hypersensitivity reactions (including anaphylaxis, angioedema, exfoliative skin conditions such as Stevens-Johnson syndrome)

Interactions

Drug-drug. Digoxin: minimally increased digoxin effect and blood level

Insulin, sulfonylureas: possible increased hypoglycemia risk

Patient monitoring

• Monitor renal function periodically.

• Measure patient's weight and body mass index periodically during therapy.

• Monitor blood glucose and hemoglobin A_1c levels periodically during therapy.

See Monitor patient for signs and symptoms of hypersensitivity reactions and immediately stop drug and institute emergency measures if such reactions occur.

• Check for diabetes signs and symptoms and disease progression routinely during therapy.

See Be aware of postmarketing reports of acute pancreatitis, including fatal and nonfatal hemorrhagic or necrotizing pancreatitis. If pancreatitis is suspected, promptly discontinue drug.

Patient teaching

• Instruct patient to take drug with or without food.

• Teach patient about signs and symptoms of hypoglycemia (such as blurred vision, confusion, tremor, sweating, excessive hunger, drowsiness, and fast heart rate).

See Teach patient about signs and symptoms of hypersensitivity reactions (such as rash, throat swelling, or difficulty breathing) and to immediately contact prescriber if these occur.

See Instruct patient to immediately discontinue drug and report if signs and symptoms of pancreatitis occur (persistent severe abdominal pain, sometimes radiating to the back, which may or may not be accompanied by vomiting).

• Instruct patient to routinely monitor blood glucose levels at home.

• As appropriate, review all other significant adverse reactions and interactions, especially those related to the drugs mentioned above.