New Pharmacological Treatment of Obesity: The Role of GLP-1 and Dual GIP/GLP-1 Receptor Agonists

Obesity is a chronic, relapsing disease associated with substantial cardiometabolic, mechanical, hepatic, renal, and psychosocial complications. Although lifestyle intervention remains the foundation of treatment, pharmacotherapy is indicated when lifestyle measures alone do not provide sufficient benefit, particularly in individuals with a body mass index of at least 30 kg/m², or at least 27 kg/m² in the presence of obesity-related complications. Incretin-based therapies have transformed obesity management by producing weight loss that approaches or exceeds that achieved with some bariatric procedures. Liraglutide, once-weekly semaglutide and tirzepatide achieve weight reduction and they have shown benefits besides weight lowering effects. Treatment selection should be individualized according to expected weight loss, obesity-related complications, tolerability, contraindications, route of administration, access, cost, and patient preference. Because discontinuation is commonly followed by weight regain and reversal of metabolic improvements, incretin-based pharmacotherapy should be regarded as long-term disease-modifying treatment. Current evidence supports a complication-centered approach in which efficacy is assessed through weight, waist circumference, glycemic control, cardiovascular risk factors, functional status, and patient-reported outcomes over time.