Sitagliptin/Metformin Extended-Release Tablets (Janumet XR) is a combination antihyperglycemic medication that plays an important role in the treatment of type 2 diabetes mellitus. To ensure medication safety and efficacy, clinicians and patients need to fully understand the precautions for use and necessary medication monitoring requirements of this drug.
What are the Precautions for Using Sitagliptin/Metformin Extended-Release Tablets (Janumet XR)?
Risk of Lactic Acidosis
Metformin-associated lactic acidosis is the most critical severe adverse reaction that requires vigilant monitoring during the use of Sitagliptin/Metformin Extended-Release Tablets, which may be fatal.
The onset of lactic acidosis is often insidious, presenting only with non-specific symptoms such as malaise, myalgia, respiratory distress, somnolence, and abdominal pain.
Severe acidosis may be accompanied by hypothermia, hypotension, and refractory bradyarrhythmias.
Risk factors include renal impairment, concurrent use of certain medications (e.g., carbonic anhydrase inhibitors), age ≥ 65 years, receipt of radiological examinations with contrast agents, surgery and other procedures, hypoxic states, excessive alcohol intake, and hepatic impairment.
If lactic acidosis is suspected, Sitagliptin/Metformin Extended-Release Tablets should be discontinued immediately, general supportive measures should be initiated in a hospital setting, and immediate hemodialysis is recommended.
Risk of Pancreatitis
After initiating Sitagliptin/Metformin Extended-Release Tablets, close monitoring of patients for signs and symptoms of pancreatitis is required.
If pancreatitis is suspected, the medication should be discontinued immediately and appropriate management measures should be implemented.
Carbonic Anhydrase Inhibitors
Carbonic anhydrase inhibitors often cause a decrease in serum bicarbonate levels and induce hyperchloremic metabolic acidosis with a normal anion gap.
Concurrent use of these agents with Sitagliptin/Metformin Extended-Release Tablets may increase the risk of lactic acidosis. More frequent monitoring of such patients should be considered.
Drugs Affecting Metformin Clearance
Concurrent use of drugs that interfere with the common renal tubular transport systems involved in the renal elimination of metformin may increase systemic exposure to metformin and potentially elevate the risk of lactic acidosis.
A risk-benefit assessment should be conducted prior to concurrent use with Sitagliptin/Metformin Extended-Release Tablets.
Insulin or Insulin Secretagogues
Concurrent use of Sitagliptin/Metformin Extended-Release Tablets with insulin secretagogues (e.g., sulfonylureas) or insulin may increase the risk of hypoglycemia.
Dose reduction of the insulin secretagogue or insulin may be required for patients receiving these medications.
Alcohol
Alcohol is known to potentiate the effects of metformin on lactate metabolism.
Patients should be advised to avoid alcohol consumption while taking Sitagliptin/Metformin Extended-Release Tablets.
Medication Monitoring for Sitagliptin/Metformin Extended-Release Tablets (Janumet XR)
Blood Glucose Monitoring
Regular monitoring of blood glucose levels is a necessary measure to evaluate the efficacy of Sitagliptin/Metformin Extended-Release Tablets.
Patients should check their blood glucose regularly as prescribed by their healthcare provider to promptly detect and manage episodes of hypoglycemia or hyperglycemia.
Hematological Parameter Monitoring
Long-term use of metformin may cause a reduction in serum vitamin B12 levels from previously normal to subnormal levels.
Hematological parameters should be measured annually, and vitamin B12 levels should be assessed every 2–3 years, with appropriate management implemented for any abnormalities detected.


