A class of drugs that mimic GLP-1, a gut hormone released after eating — they stimulate insulin, suppress appetite, and slow digestion, making them the most effective pharmaceutical weight loss tools currently available.Mechanism: glucose-dependent insulin secretion (safe — no hypoglycemia at normal glucose levels), glucagon suppression, gastric emptying delay, and hypothalamic satiety signaling. The glucose-dependence is the key safety feature that differentiates GLP-1 agonists from insulin. Includes semaglutide, liraglutide, and tirzepatide (GLP-1/GIP dual agonist). The most clinically successful class of metabolic peptide therapeutics to date, with Phase III trial data far exceeding any other compound in the weight loss space.