BRAND NAMES
 MECHANISM OF ACTION
Metformin/Sitagliptin ombines two antidiabetic medications with complementary mechanisms of action to improve glycemic control in patients with type 2 diabetes: sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, and metformin hydrochloride, a member of the biguanide class.
Metformin/Sitagliptin is indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus when treatment with both sitagliptin and metformin is appropriate.
Limitations of Use:
- Metformin/Sitagliptin should not be used in patients with type 1 diabetes or for the treatment of diabetic ketoacidosis.
- Metformin/Sitagliptin has not been studied in patients with a history of pancreatitis
- Individualize the starting dose of Metformin/Sitagliptin based on the patient’s current regimen.
- May adjust the dosing based on effectiveness and tolerability while not exceeding the maximum recommended daily dose of 100 mg sitagliptin and 2000 mg metformin.
- Metformin/Sitagliptin should be given twice daily with meals, with gradual dose escalation, to reduce the gastrointestinal (GI) side effects due to metformin. The extended release tablets (JANUMET XR) should be administered once daily with a meal preferably in the evening.
- Renal dysfunction, e.g., serum creatinine ≥1.5 mg/dL [males], ≥1.4 mg/dL [females] or abnormal creatinine clearance.
- Metabolic acidosis, including diabetic ketoacidosis.
- History of a serious hypersensitivity reaction to Metformin/Sitagliptin or sitagliptin, such as anaphylaxis or angioedema
 WARNINGS AND PRECAUTIONS
- Lactic acidosis is a very rare (0.03 cases/1000 patient/year), but serious, metabolic complication that can occur due to metformin accumulation (primarily reported in diabetic patients with significant renal failure). The risk increases also with conditions such as sepsis, dehydration, excess alcohol intake, hepatic impairment, and acute congestive heart failure. Symptoms include respiratory distress, abdominal pain , malaise, myalgias, increasing somnolence and hypothermia. If metabolic acidosis is suspected, treatment with the medicinal product should be discontinued and the patient hospitalised immediately. Warn against excessive alcohol intake. Metformin/Sitagliptin is not recommended in hepatic impairment and is contraindicated in renal impairment. Ensure normal renal function before initiating and at least annually thereafter.
- Temporarily discontinue Metformin/Sitagliptin in patients undergoing radiologic studies with intravascular administration of iodinated contrast materials or any surgical procedures necessitating restricted intake of food or fluids.
- There have been postmarketing reports of acute pancreatitis, including fatal and non-fatal hemorrhagic or necrotizing pancreatitis. If pancreatitis is suspected, promptly discontinue Metformin/Sitagliptin.
- There have been postmarketing reports of acute renal failure, sometimes requiring dialysis. Before initiating Metformin/Sitagliptin and at least annually thereafter, assess renal function and verify as normal.
- Vitamin B12 deficiency: Metformin may lower Vitamin B12 levels. Measure hematologic parameters annually.
- When used with an insulin secretagogue (e.g., sulfonylurea) or with insulin, a lower dose of the insulin secretagogue or insulin may be required to reduce the risk of hypoglycemia.
- There have been postmarketing reports of serious allergic and hypersensitivity reactions in patients treated with sitagliptin (one of the components of Metformin/Sitagliptin), such as anaphylaxis, angioedema, and exfoliative skin conditions including Stevens-Johnson syndrome. In such cases, promptly stop Metformin/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 Metformin/Sitagliptin or any other anti-diabetic drug.
- Cationic drugs eliminated by renal tubular secretion: Use with caution.
 PREGNANCY AND LACTATION
- Pregnancy Category B (US). Metformin/Sitagliptin should be used during pregnancy only if clearly needed.
- Nursing Mothers : In studies performed with the individual components, both sitagliptin and metformin are secreted in the milk of lactating rats. It is not known whether sitagliptin is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when this drug is administered to a nursing woman.
 SIDE EFFECTS
- The most common adverse reactions reported in ≥5% of patients simultaneously started on sitagliptin and metformin and more commonly than in patients treated with placebo were diarrhea, upper respiratory tract infection, and headache.
- Adverse reactions reported in ≥5% of patients treated with sitagliptin in combination with sulfonylurea and metformin and more commonly than in patients treated with placebo in combination with sulfonylurea and metformin were hypoglycemia and headache.
- Hypoglycemia was the only adverse reaction reported in ≥5% of patients treated with sitagliptin in combination with insulin and metformin and more commonly than in patients treated with placebo in combination with insulin and metformin.
 RELATED LINKS
- http://www.merck.com/product/usa/pi_circulars/j/janumet/janumet_pi.pdf (Revised: 02/2014)
- http://www.merck.com/product/usa/pi_circulars/j/janumet_xr/janumet_xr_pi.pdf (Revised: 02/2014)
|Diabetes (Antidiabetic drugs)|
|Insulin Secretagogues (drugs that increase insulin release from pancreas)||Sulfonylureas||Chlorpropamide (Diabinese) • Glibenclamide or Glyburide (Diabeta, Micronase, Glynase, Daonil, Euglycon) • Gliclazide (Diamicron) • Glimepiride (Amaryl, Solosa) • Glipizide (Glucotrol, Minidiab, Glibenese) • Gliquidone (Glurenorm)|
|Meglitinides||Repaglinide (Prandin, Novonorm) • Nateglinide (Starlix)|
|Dipeptidyl peptidase-4 inhibitors||Linagliptin (Trajenta) • Saxagliptin (Onglyza) • Sitagliptin (Januvia) • Vildagliptin (Galvus)|
|Incretin mimetics (GLP-1 agonists and analogs)||Exenatide (Byetta) • Liraglutide (Victoza) • Lixisenatide (Lyxumia) • Dulaglutide (Trulicity)|
|Insulin Sensitizers (drugs that decrease insulin resistance)|
|Drugs that retard the digestion and absorption of carbohydrates in the small intestine|
|Alpha-glucosidase inhibitors||Acarbose (Glucobay, Precose)|
|Drugs that reduce glucose absorption in the kidney and increase glucose excretion in the urine|
|Sodium glucose cotransporter 2 (SGLT2) inhibitors||Canagliflozin (Invokana) • Dapagliflozin (Farxiga) • Empagliflozin (Jardiance, Glyxambi, Synjardi)|
|Insulin and insulin analogs|
|Intermediate acting insulins||Insulin lispro protamine (Humalog BASAL) • Isophane human insulin : Human insulin protamine (NPH) (Humulin I, Protaphane)|
|Long-acting insulins||Insulin detemir (Levemir) • Insulin glargine (Lantus)|
|Fast-acting insulins||Regular insulin : Insulin (Human recombinant) (Actrapid, Humulin R)|
|Ultra-rapid-acting insulins||Insulin aspart (Novorapid) • Insulin glulisine (Apidra) • Insulin lispro (Humalog) • Insulin human (Inhalation Powder) (Afrezza)|
|Premixed insulin (ultra-rapid-acting + intermediate acting||Insulin aspart / Insulin aspart protamine (Novomix) • Insulin lispro / Insulin lispro protamine (Humalog Mix)|
|Inhaled Insulin||Insulin human (Inhalation Powder) (Afrezza)|
|Sulfonylurea + Metformin||Glibenclamide / Metformin (Bieuglicon M, Diaglimet, Glibomet, Gliconorm, Glicorest, Suguan M)|
|Thiazolidinedione + Metformin||Pioglitazone / Metformin (Competact, Glubrava)|
|Thiazolidinedione + Sulfonylurea||Pioglitazone / Glimepiride (Tandemact)|
|Dipeptidyl peptidase-4 inhibitors + Metformin||Linagliptin / Metformin (Jentadueto) • Sitagliptin / Metformin (Efficib, Janumet, Velmetia) • Vildagliptin / Metformin (Eucreas)|