Linagliptin: Linagliptin is an inhibitor of DPP-4, an enzyme that degrades the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Thus, Linagliptin increases the concentrations of active incretin hormones, stimulating the release of insulin in a glucose-dependent manner and decreasing the levels of glucagon in the circulation. Both incretin hormones are involved in the physiological regulation of glucose homeostasis. Incretin hormones are secreted at a low basal level throughout the day and levels rise immediately after meal intake. GLP-1 and GIP increase insulin biosynthesis and secretion from pancreatic beta cells in the presence of normal and elevated blood glucose levels. Furthermore, GLP-1 also reduces glucagon secretion from pancreatic alpha cells, resulting in a reduction in hepatic glucose output.
Metformin: Metformin lowers both basal and postprandial plasma glucose. It does not stimulate insulin secretion and therefore does not produce hypoglyceamia or increased weight gain. Metformin may exert its glucose-lowering effect via four mechanisms:
- by reduction of hepatic glucose production through inhibition of gluconeogenesis and glycogenolysis;
- in muscle, by modestly increasing insulin sensitivity, improving peripheral glucose uptake and utilization;
- by delaying intestinal glucose absorption;
- stimulate intracellular glycogen synthesis by acting on glycogen synthase and increase the transport capacity of glucose transporters (GLUT-1 & GLUT-4)
Dosage & Administration
Recommended starting dose: In patients currently not treated with Metformin, initiate treatment with 2.5 mg Linagliptin and 500 mg Metformin Hydrochloride twice daily. In patients already treated with Metformin, start with 2.5 mg Linagliptin and the current dose of Metformin Hydrochloride twice daily. Patients already treated with linagliptin and metformin, individual components may be switched to this combination containing the same doses of each component.