Generic Name and Formulations:
Sitagliptin, metformin (as HCl); 50mg/500mg, 50mg/1000mg; tabs.
Merck & Co., Inc.
Indications for JANUMET:
Adjunct to diet and exercise to improve glycemic control in patients with type 2 diabetes when treatment with both sitagliptin and metformin is appropriate.
Limitations Of use:
Not for treatment of type 1 diabetes or diabetic ketoacidosis. Not studied in patients with history of pancreatitis.
Individualize. Swallow whole. Take with food. Not currently treated with metformin: initially 50mg/500mg twice daily. Previously on metformin alone: initially 50mg twice daily of sitagliptin plus metformin dose. Previously on metformin 850mg twice daily: start with 50mg/1000mg twice daily. Previously on sitagliptin and metformin: switch on a mg/mg basis. May titrate gradually up to max 100mg sitagliptin/2000mg metformin per day. Renal impairment (eGFR 30–<45mL/min/1.73m2): not recommended.
<18yrs: not established.
Severe renal impairment (eGFR <30mL/min/1.73m2). Metabolic acidosis, diabetic ketoacidosis.
Increased risk of metformin-associated lactic acidosis in renal or hepatic impairment, concomitant use of certain drugs (eg, cationic drugs), ≥65yrs of age, undergoing radiological contrast study, surgery and other procedures, hypoxic states, and excessive alcohol intake; discontinue if lactic acidosis occurs. Discontinue at time of, or prior to intravascular iodinated contrast imaging in patients with eGFR 30–60mL/min/1.73m2, history of hepatic impairment, alcoholism, hypoxemia, or will be given intra-arterial contrast; reevaluate eGFR 48hrs after procedure and restart therapy if renally stable. Suspend therapy if dehydration occurs or before surgery. Avoid if clinical or lab evidence of hepatic disease. Consider risks/benefits in patients with known risk factors for heart failure; monitor for signs/symptoms; evaluate and consider discontinuing if develops. Assess renal function prior to starting and periodically thereafter; more frequently in elderly or if eGFR <60mL/min/1.73m2. Discontinue if pancreatitis, serious hypersensitivity reactions, severe joint pain, or bullous pemphigoid is suspected or occurs. History of angioedema to other DPP-4 inhibitors. Elderly, debilitated, uncompensated strenuous exercise, malnourished or deficient caloric intake, adrenal or pituitary insufficiency, or alcohol intoxication: increased risk of hypoglycemia. Monitor hematology (esp. serum Vit. B12 in susceptible patients). Pregnancy. Nursing mothers.
Dipeptidyl peptidase-4 (DPP-4) inhibitor + biguanide.
Increased risk of lactic acidosis with topiramate, other carbonic anhydrase inhibitors (eg, zonisamide, acetazolamide, dichlorphenamide); monitor. Concomitant cationic drugs that interfere with renal tubular transport systems (eg, ranolazine, vandetanib, dolutegravir, cimetidine) may increase metformin levels; monitor. Avoid excessive alcohol intake (potentiates effects of metformin on lactate). Diuretics, steroids, phenothiazines, thyroid products, estrogens, oral contraceptives, phenytoin, sympathomimetics, calcium channel blockers, isoniazid, nicotinic acid, others may cause hyperglycemia. May need lower dose of concomitant sulfonylurea or insulin to reduce risk of hypoglycemia. β-blockers may mask hypoglycemia. Monitor digoxin.
Diarrhea, URTI, headache, nasopharyngitis, hypoglycemia; pancreatitis, hypersensitivity reactions, severe and disabling arthralgia; rare: lactic acidosis (may be fatal).
Tabs—60, 180, 1000; XR tabs 50mg/500mg, 50mg/1000mg—60, 180, 1000; 100mg/1000mg—30, 90, 1000