The main difference between Mounjaro and Wegovy lies in how they work: Mounjaro (tirzepatide) mimics two hormones GLP-1 (glucagon-like peptide-1) and GIP( (glucose-dependent insulinotropic polypeptide) ) making a dual-action treatment that helps control appetite, improve blood sugar, and boost fat metabolism. Wegovy (semaglutide) mimics just GLP-1, helping reduce hunger and increase feelings of fullness.