Assistant Lecturer Hanadi Hadi Medications like Ozempic and Wegovy (semaglutide) and Mounjaro and Zepbound (tirzepatide) used recently as weight loss drugs differ in their mechanism of action: Ozempic and Wegovy are glucagon like peptide 1 (GLP-1) receptor agonists. These drugs mimic the action of the GLP-1 hormone, which plays a vital role in regulating appetite and insulin secretion resulting in reduced caloric intake and weight loss. GLP-1 hormone has many actions: in the gut it facilitates digestion, improves nutrient absorption and slows gastric emptying; in the brain it helps regulation of appetite, signalling feelings of fullness and reducing hunger; in the pancreas, it stimulates the release of insulin to manage blood sugar levels and also suppresses glucagon. These actions together help regulate energy balance in the body and maintain blood sugar levels stay within healthy limits. Mounjaro mimics the action of two hormones: (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) that stimulate insulin secretion and decrease glucagon secretion. GIP also plays a role in nutrient and energy metabolism. Thus, Mounjaro has a dual agonism action making a synergistic effect that extends from the gut to the central nervous system with a greater weight loss. Al-Mustaqbal University – The Leading University in Iraq