Janumet is a prescription medication composed of two medications: Sitagliptin and metformin. It is used for the management of type 2 diabetes when sitagliptin or metformin alone does not control blood sugar levels adequately. Janumet contains 50mg of sitagliptin and 500 or 1000 mg of metformin. Your physician will decide the dosage of the drug that is safe for you.
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Sitagliptin is a dipeptidyl peptidase IV inhibitor and metformin is a biguanide. Sitagliptin blocks the dipeptidyl peptidase IV enzyme, which results in an increase in insulin production. It also decreases the release of glucagon, the hormone that raises blood sugar levels. If glucagon is low, the liver produces less glucose. Metformin decreases liver glucose production, decreases absorption of glucose in the stomach and improves insulin sensitivity, according to the "Drug Information Handbook." The combination of the two medications enables the body to control blood sugar levels effectively.
Elevated Liver Enzymes
The liver enzymes aspartate transaminase and alanine transaminase are the most commonly found enzymes. Other enzymes include alkaline phosphatase and gamma-glutamyl transferase. Sitagliptin may elevate the liver enzymes; this side effect has been seen during postmarketing surveillance, which is reported by patients and health care professionals.
Liver Impairment
Patients who have liver impairment should avoid the use of Janumet because the use of metformin in liver disease can increase the risk of developing lactic acidosis. Lactic acidosis is the buildup of lactic acid, a chemical compound involved in many cellular processes. The compound builds up faster than the body is able to remove it. Symptoms of lactic acidosis include nausea and weakness.
Electrolytes, which include sodium, potassium, chloride and bicarbonate, are usually measured to determine if levels are low. Patients who have severe liver impairment or who have a history of lactic acidosis should not use Janumet, according to "Pharmacotherapy: A Pathophysiologic Approach."
Monitoring
Your physician can monitor you appropriately so do not skip your appointments. A routine blood test can measure fasting glucose and HbA1c, which measures your blood sugar levels over the prior six months. Liver function tests, which determine the health of the liver and can indicate liver dysfunction, must be done periodically, as well. Tell your physician about all the medications you use and whether you have a history of liver dysfunction to avoid serious reactions.
References
- "Drug Information Handbook"; Charles F. Lacy, Lora L. Armstrong, et al.; 2009
- "Pharmacotherapy: A Pathophysilogic Approach"; Joseph T. DiPiro, Robert L. Talbert,et al.; 2008
- PubMed Health: Lactic Acidosis
