Metformin-sitagliptin

1-10%

Abdominal pain (2.2%)

Diarrhea (2.4%)

Hypoglycemia (2.1%)

Nausea (1.3%)

Vomiting (1.1%)

Frequency Not Defined

Exfoliative disorder of skin of scalp

Stevens-Johnson syndrome

Lactic acidosis (rare )

Anaphylaxis/hypersensitivity reaction

Rhabdomyolysis

Acute renal failure

Angioedema

Postmarketing Reports

Hypersensitivity reactions including anaphylaxis, angioedema, rash, urticaria, cutaneous vasculitis, and exfoliative skin conditions including Stevens-Johnson syndrome

Upper respiratory tract infection

Hepatic enzyme elevations

Acute pancreatitis including fatal and nonfatal hemorrhagic and necrotizing pancreatitis

Gastrointestinal: Constipation, vomiting

Neurologic: Headache

Worsening renal function, including acute renal failure (sometimes requiring dialysis)

Myalgia, pain in extremity, and back pain

Severe disabling arthralgia

Pruritus

Mechanism of Action

Sitagliptin: Dipeptidyl peptidase 4 (DPP-4) inhibitor, thereby increasing and prolonging incretin hormone activity which are inactivated by DPP-4 enzyme. Incretins increase insulin release and synthesis from pancreatic beta cells and reduce glucagon secretion pancreatic alpha cells

Metformin: Biguanide; acts by decreasing endogenous hepatic glucose production, decreases intestinal absorption of glucose, and improves insulin sensitivity by increasing peripheral glucose uptake and utilization; improves glucose tolerance and lowers both basal and postprandial plasma glucose

Pharmacokinetics

Half-Life

• Sitagliptin: ~12.4 hr
• Metformin: ~6.2 hr

Bioavailability

• Sitagliptin: 87%
• Metformin: 50-60%

Excretion

• Sitagliptin: Urine 79%
• Metformin: Urine 90%

Sitagliptin/metformin is a prescription medication used to treat type 2 diabetes in adults.

Sitagliptin/metformin is a single tablet containing 2 prescription drugs. Sitagliptin belongs to a group of drugs called dipeptidyl peptidase-4 (DPP-4) inhibitors, which help lower blood sugar levels. Metformin belongs to a group of drugs called biguanides, which decrease the amount of sugar made by the liver and help cells to respond to insulin.

This medication comes in tablet form and is taken twice a day, with meals.

Sitagliptin/metformin is also available as an extended release tablet and is taken once a day with a meal preferably in the evening. Take sitagliptin/metformin extended release tablets whole. Do not break, cut, crush, dissolve, or chew sitagliptin/metformin extended release tablets before swallowing. If you cannot swallow Janumet XR tablets whole, tell your doctor.

Common side effects include stuffy nose, headache, sore throat, nausea, vomiting, and diarrhea.

Metformin & Sitagliptin may be found in some form under the following brand names:

• Janumet

• Janumet XR

Metformin & Sitagliptin is part of the drug class:

• Combinations of oral blood glucose lowering drugs

Serious side effects have happened in people taking sitagliptin/metformin (see "Drug Precautions"). 

The most common side effects of sitagliptin/metformin include:

• stuffy or runny nose and sore throat
• upper respiratory infection
• diarrhea
• nausea and vomiting
• gas, upset stomach, indigestion
• weakness
• headache

Taking sitagliptin/metformin with meals can help lessen the common stomach side effects of metformin that usually happen at the beginning of treatment. If you have unusual or sudden stomach problems, talk with your doctor. Stomach problems that start later during treatment may be a sign of something more serious. Sitagliptin/metformin may have other side effects, including:

• Swelling of the hands or legs.
• Swelling of the hands and legs can happen if you take sitagliptin/metformin in combination with rosiglitazone (Avandia). Rosiglitazone is another type of diabetes medicine.
• Low blood sugar (hypoglycemia). If you take sitagliptin/metformin with another medicine that can cause low blood sugar, such as a sulfonylurea or insulin, your risk of getting low blood sugar is higher. The dose of your sulfonylurea medicine or insulin may need to be lowered while you use sitagliptin/metformin. Signs and symptoms of low blood sugar may include: 
• headache
• drowsiness
• weakness
• dizziness
• confusion
• irritability
• hunger
• fast heart beat
• sweating
• feeling jittery

Medicines can interact with certain foods. In some cases, this may be harmful and your doctor may advise you to avoid certain foods. In the case of sitagliptin/metformin there are no specific foods that you must exclude from your diet when receiving this medication.

If you take too much sitagliptin/metformin (more than the prescribed dose), call your local Poison Control Center right away.