University of Pennsylvania School of Medicine Nov 17 2025 A rare glimpse into the brain activity of a patient with obesity and loss of control eating on tirzepatide, marketed as Mounjaro and Zepbound, revealed that the medication suppresses signaling in the brain's "reward center" thought to be involved in food noise – but only temporarily. Research suggests that the medication, a glucagon -like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptor agonist,