Shopper Approved Rating

Have a prescription? Buy Janumet from Canada and enjoy a host of benefits, including:

  • Cost Savings: Buy Janumet at prices significantly lower than the US
  • Reliable Express Shipping: Quick and efficient delivery straight to your door
  • Easy Ordering: Securely place orders online or by phone at 1-888-525-1815
  • Trusted by THOUSANDS of Americans
  • SAVE 10% on first order with coupon code: FIRST10
Janumet (Metformin Hydrochloride, Sitagliptin)
Sitagliptin Phosphate, Metformin Hydrochloride
Select product strength & quantity:
Select product strength & quantity:
Select product strength & quantity:

Prescription Required.

Product of Canada.

Express Ships from Canada.

Prescription Required.
Product of Canada.
Express Ships from Canada.

What is Janumet

Janumet is an oral medication that includes a combination of two antidiabetic medications, metformin and sitagliptin. It is indicated in adults with type 2 diabetes mellitus (T2DM) to improve glycemic control in addition to diet and exercise. Controlling hyperglycemia prevents downstream complications such as kidney damage, loss of limbs, blindness, heart attack, stroke, or nerve problems. It is important that diabetes remains controlled to lessen the chance of related complications. Janumet is not indicated for the treatment of  type I diabetes.

How does Janumet Work?

Metformin, a biguanide, and sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, work together through a complementary mechanism to improve glycemic control. The individual components of Janumet work in the following ways:


Incretin hormones are important in glycemic control and include glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). After meals, the intestine releases these incretin hormones in response to increased blood glucose concentrations. These hormones stimulate insulin release from pancreatic beta cells, thus regulating the blood glucose levels. However, GLP-1 and GIP can be inactivated by an enzyme called DPP-4. Sitagliptin inhibits DPP-4, thus increasing incretin hormone levels and insulin release to mediate blood sugar levels.


Metformin is a biguanide that lowers the production of hepatic glucose, lowers absorption of glucose in the intestine, and improves insulin sensitivity through increasing peripheral glucose. Insulin release does not change with metformin, however, fasting levels of insulin and day-long plasma insulin response can be lowered.

Side Effects

Common side effects include:

  • Nausea, vomiting, or stomach upset
  • Diarrhea or constipation
  • Headache
  • Joint or muscle pain
  • Back pain
  • Weakness
  • A metallic taste in the mouth
  • Cold symptoms such as runny or stuffy nose, sneezing, and sore throat

Warnings & Precautions

Lactic acidosis

There have been multiple reports of lactic acidosis with metformin use, with some being fatal cases. Onset was typically gradual with symptoms including muscle pain, abdominal pain, drowsiness, and respiratory distress. More severe cases of acidosis included symptoms such as hypothermia, hypotension, and bradyarrhythmias. The signs and symptoms were accompanied by increased blood lactate concentrations, anion gap acidosis, and an elevated lactate/pyruvate ratio. There are multiple risk factors that increase an individual’s chance of developing lactic acidosis while on metformin. Risk factors and subsequent risk reduction measures include:

  • Renal impairment – Do not use in patients with an eGFR of less than 45 mL/min/1.73 m2
  • Age 65 or greater – Assess renal function more often
  • Radiological studies with contrast – Discontinue Janumet prior to an iodinated contrast imaging procedure in certain patients
  • Surgery – Hold Janumet while patients have restricted food and fluid intake
  • Hypoxic states – Stop Janumet when hypoxic states occur, such as in acute congestive heart failure, cardiovascular collapse, acute myocardial infarction, and sepsis
  • Alcohol – Avoid excessive alcohol intake
  • Hepatic impairment – Do not use Janumet if patient exhibits signs of hepatic disease


Both fatal and non-fatal hemorrhagic or necrotizing acute pancreatitis cases have been reported. If a patient experiences any signs or symptoms of pancreatitis, Janumet should be stopped immediately and the pancreatitis should be managed appropriately.

Heart Failure

Other DPP-4 inhibitors have demonstrated an association with heart failure. Take caution when using Janumet in patients with a history of heart failure or renal impairment, and monitor therapy closely. If heart failure occurs while taking Janumet, consider stopping therapy.

Acute Renal Failure

There have been cases of worsening renal function, such as acute renal failure and the need for dialysis. Renal function should be evaluated before initiation of Janumet and throughout therapy. If renal dysfunction is expected to develop, like in the elderly, renal function should be evaluated more often. Stop Janumet in the case of renal impairment.

Vitamin B12 Deficiency

Studies have shown a decrease in vitamin B12 levels with the use of metformin. Monitor hematologic measures annually and vitamin B12 parameters every 2 to 3 years for patients taking Janumet. If abnormalities are present, manage appropriately with Janumet discontinuation or vitamin B12 supplementation.

Hypoglycemia with Concomitant Use of Insulin Products

Janumet can cause hypoglycemia when used in combination with other products that lower blood glucose, such as insulin. Dose adjustments to insulin may be required to prevent development of hypoglycemia.

Hypersensitivity Reactions

Sitagliptin has been shown to cause severe hypersensitivity reactions, including anaphylaxis, angioedema, and Stevens-Johnson syndrome within 3 months of starting Janumet. If these events occur, Janumet should be discontinued and alternative therapies should be explored.

Severe and Disabling Arthralgia

DPP-4 inhibitors have demonstrated severe and disabling arthralgias that subside upon drug withdrawal. If experiencing pain in one’s joints, patients should stop taking Janumet and avoid other DPP-4 inhibitors.

Bullous Pemphigoid

Monitor patients for the formation of erosions or blisters, as there have been reported cases of bullous pemphigoid with DPP-4 inhibitors. Treatment of this phenomenon usually requires hospitalization and immunosuppressive therapy. If suspected, discontinue Janumet and obtain a dermatologist referral.

Drug Interactions

Carbonic Anhydrase Inhibitors (CAI)

Carbonic anhydrase inhibitors can lower serum bicarbonate and cause non-anion gap metabolic acidosis. When used concomitantly with Janumet, this combination can elevate an individual’s risk for developing lactic acidosis. Patients that are taking these drugs in combination should be frequently monitored. Examples of CAIs include topiramate and acetazolamide.

Drugs that Decrease Clearance of Metformin

Medications that interfere with the renal elimination of metformin should be avoided. Drugs like ranolazine, dolutegravir, and cimetidine can increase a patient’s systemic exposure to metformin and elevate the risk of lactic acidosis.

Alcohol Consumption

Patients should avoid excessive alcohol intake. Alcohol has been shown to increase metformin’s effect on lactate metabolism, causing increased risk for lactic acidosis.

Other Drugs Affecting Glycemic Control

When used in combination with other drugs that can cause hypoglycemia (such as thiazide and other diuretics), the risk for developing hypoglycemia with Janumet is increased. Patients should be monitored for signs of hypoglycemia when on concomitant glucose-altering agents such as steroids, diuretics, and phenytoin.

Other Drug Interactions

  • ACE inhibitors
  • beta-2-agonists
  • calcium channel blocking drugs
  • corticosteroids
  • estrogens or estrogens plus progestogen
  • isoniazid
  • nicotinic acid
  • oral contraceptives
  • phenothiazines
  • phenytoin,
  • sympathomimetics
  • thyroid products

Frequently Asked Questions

Janumet is a medication used for treating type 2 diabetes, it is made up of two active ingredients sitagliptin and metformin.

If you miss a dose of Janumet, take the dose as soon as you remember. If it is time for the next dose at the time that you remember, skip the missed dose and return to your normal dosing schedule. Do not take more than one dose of Janumet at the same time.

Janumet can be taken long term to control type II diabetes mellitus.

Janumet can be taken with food to avoid side effects such as an upset stomach.

If you overdose with Janumet, you should immediately go to the emergency room or contact the Poison Control Center. Overdosing on Janumet increases an individual’s chance of developing hypoglycemia or lactic acidosis.

Avoid excessive alcohol intake, as this increases one’s risk of developing lactic acidosis while on Janumet.

Common side effects of Janumet include:

  • Cold symptoms such as a sore throat or stuffy or runny nose
  • Upset stomach, bloating, and indigestion
  • Headache
  • Nausea, vomiting, and diarrhea
  • Weakness
  • Upper respiratory infection
  • Low blood sugar
  • Joint or muscle pain
  • Metallic taste in the mouth

It is important that you tell your doctor all of the medications, vitamins, and supplements that you take. Additionally, tell your doctor if you:

  • Have inflammation of your pancreas (pancreatitis)
  • Have kidney problems
  • Have liver problems
  • Have heart failure
  • Drink alcohol frequently or drink large amounts of alcohol at once (“binge” drinking)
  • Will be receiving injection of dye or contrast agents for an x-ray procedure
  • Have low vitamin B12 levels in your blood
  • Are pregnant or plan to become pregnant
  • Are breastfeeding or plan to breastfeed
  • Are a premenopausal woman

Janumet works by increasing the amount of insulin produced by the pancreas in response to high blood sugar, in addition to decreasing the amount of sugar produced by the liver.

Janumet is primarily prescribed to adults with type 2 diabetes. It should not be used by individuals with type 1 diabetes or those who have diabetic ketoacidosis.

Prior to starting treatment using Janumet, inform your doctor if you have any history of kidney or liver disease, or heart problems. Also, let your doctor know if you are pregnant or planning to become pregnant while taking this medication.

Janumet should be taken with meals to reduce the risk of stomach side effects. The dosage will be determined by your doctor based on your blood sugar levels and other factors.

If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the next dose at your regular time. Do not take extra medicine to make up for a missed dose.