Glucagon-like peptide 1 (GLP-1) is a hormone that is released from cells in our intestines and colon when we eat food. When GLP-1 binds to its receptor, it stimulates the release of insulin and inhibits the release of glucagon by the pancreas. GLP-1 receptors are located throughout the body, and therefore, the binding of GLP-1 can have effects unrelated to blood glucose lowering, including increased feelings of fullness and satiety, reduced hunger, and decreased food intake.[1]
Synthetic GLP-1 agonists such as liraglutide, semaglutide, and terzepatide mimic the effects of GLP-1 in the body. Furthermore, synthetic GLP-1 agonists have a longer half-life in the body than the native hormone, making for longer-lasting therapeutic effects. Specifically, while the half-life of native GLP-1 is 1–2 minutes, the half-life of GLP-1 analogs can range from 11–15 hours (liraglutide) to 155–184 hours (semaglutide), allowing semaglutide to be administered just once per week by subcutaneous injection.[2]