Janumet

Janumet is a combination oral antidiabetic medication containing sitagliptin and metformin hydrochloride.

It is prescribed for the management of type 2 diabetes mellitus in adults when treatment with metformin alone, or metformin combined with a DPP-4 inhibitor given separately, does not provide adequate glycaemic control.

Sitagliptin is a dipeptidyl peptidase-4 (DPP-4) inhibitor that works by prolonging the activity of incretin hormones, GLP-1 and GIP.

These hormones stimulate insulin secretion from the pancreas and suppress glucagon release in a glucose-dependent manner, meaning they are most active when blood sugar is elevated.

Metformin reduces hepatic glucose production, decreases intestinal absorption of glucose, and improves insulin sensitivity in peripheral tissues.

By combining these two complementary mechanisms in a single tablet, Janumet offers convenient and effective blood glucose lowering with a low risk of hypoglycaemia.

The fixed-dose combination also simplifies treatment regimens, which can improve adherence and long-term outcomes in diabetes management.

Take Janumet by mouth twice daily with meals, as taking it with food reduces the gastrointestinal side effects of metformin. Swallow tablets whole with a glass of water.

Follow the dosage prescribed by your doctor and do not adjust your dose without medical advice. Regular blood glucose monitoring is recommended.

Continue with dietary measures and exercise as advised by your healthcare team.

Janumet is available in several strengths: 50 mg/500 mg, 50 mg/850 mg, and 50 mg/1,000 mg (sitagliptin/metformin). The dose is individualised based on the patient's current regimen and tolerance.

The usual dose is one tablet twice daily. The maximum daily dose of sitagliptin is 100 mg and of metformin is 2,000 mg.

Dose adjustment is required in patients with moderate renal impairment; Janumet is not recommended in severe renal impairment.

Common (1 in 10 to 1 in 100): nausea, diarrhoea, vomiting, flatulence, headache, hypoglycaemia (when used with a sulphonylurea or insulin).

Uncommon (1 in 100 to 1 in 1,000): dizziness, constipation, somnolence, upper respiratory tract infection. Rare (1 in 1,000 to 1 in 10,000): pancreatitis, lactic acidosis (attributable to metformin).

Very rare (less than 1 in 10,000): severe hypersensitivity reactions, bullous pemphigoid.

Seek immediate attention if you experience persistent severe abdominal pain, as this may indicate pancreatitis.

The metformin component carries a risk of lactic acidosis, a rare but serious complication, particularly in patients with renal impairment, hepatic insufficiency, dehydration, or acute illness.

Renal function should be assessed before starting and periodically during treatment.

Janumet should be temporarily withheld around surgical procedures and radiological investigations involving iodinated contrast media.

Reports of pancreatitis have been associated with DPP-4 inhibitors; patients should be counselled about the symptoms of pancreatitis.

Janumet is contraindicated in patients with type 1 diabetes, diabetic ketoacidosis, severe renal impairment (eGFR below 30 ml/min), conditions predisposing to lactic acidosis (including severe infection, dehydration, shock, and acute heart failure), and known hypersensitivity to sitagliptin, metformin, or any of the excipients.

It should not be used in patients with severe hepatic impairment.