Jentin Met Tab is a prescription medication that combines two active ingredients, sitagliptin and metformin HCI. It is commonly used for the treatment of type 2 diabetes. Sitagliptin works by raising the body's incretin hormone levels, which promote the pancreas to produce more insulin and decrease the amount of glucose the liver produces to assist control blood sugar levels. Metformin HCI works by lowering the amount of glucose the liver releases and increasing the body's sensitivity to insulin. The medicine should be taken orally with a meal to reduce the risk of stomach upset. It is usually taken once or twice daily, as directed by the doctor.