Bind to nuclear peroxisome proliferator-activating receptors (PPARs) involved in transcription of insulin responsive genes sensitization of tissues to insulin, plus in hepatic gluconeogenesis and triglycerides and insulin receptor numbers
Adverse effects: less hypoglycemia than sulfonylureas, but weight gain and edema reported
Synthetic analog of amylin
Injectable: modulates postprandial glucose levels
Suppresses glucagon release via undetermined mechanisms, delays gastric emptying, and has central nervous system-mediated anorectic effects
Administered in addition to insulin in those who are unable to achieve their target postprandial blood sugars
Renal metabolism and excretion
Always be injected by itself with a separate syringe; it cannot be mixed with insulin
Adverse effects: hypoglycemia and gastrointestinal symptoms including nausea, vomiting, and anorexia.
A synthetic analog of glucagon-like-polypeptide 1 (GLP-1), exenatide is the first incretin therapy to become available for the treatment of diabetes
Approved as an injectable, adjunctive therapy in persons with type 2 diabetes treated with metformin or metformin plus sulfonylureas who still have suboptimal glycemic control
potentiation of glucose-mediated insulin secretion
Suppression of postprandial glucagon release through as-yet unknown mechanisms
slowed gastric emptying, and a central loss of appetite
The increased insulin secretion is speculated to be due in part to an increase in beta-cell mass
Adverse effects are nausea (about 44% of users) and vomiting and diarrhea. The nausea decreases with ongoing exenatide usage
Weight loss is reported in some users, presumably because of the nausea and anorectic effects. A serious and, in some cases, fatal adverse effect of exenatide is necrotizing and hemorrhagic pancreatitis.
Safety issues, however, may deter future use.
Inhibitor of dipeptidyl peptidase-4 (DPP-4), the enzyme that degrades incretin and other GLP-1-like molecules
Its major action is to increase circulating levels of GLP-1 and GIP.
Decreases postprandial glucose excursions by increasing glucose-mediated insulin secretion and decreasing glucagon levels
Adverse effects include
nasopharyngitis, upper respiratory infections, and headaches. Rarely, severe allergic reactions
Dosage should be reduced in patients with renal impairment. Sitagliptin can be given as monotherapy or combined with metformin or Tzds.