Comparative Effectiveness of Semaglutide, Liraglutide, Orlistat, and Phentermine for Weight Loss in Obese Individuals: A Systematic Review.

Obesity, a multifaceted and chronic condition characterized by excessive fat accumulation, poses significant risks to overall health and is associated with various metabolic and cardiovascular complications. This literature review evaluates and compares the effectiveness of four pharmacological agents semaglutide, liraglutide, orlistat, phentermine, and emerging agents like setmelanotide, amycretin, retatrutide, cagrilintide, and cotadutide in managing weight loss among obese. A detailed analysis was conducted on their mechanisms of action, dosing regimens, efficacy in weight loss, safety profiles, and their impact on obesity-related comorbidities. Although all agents presented distinct benefits, side effects such as gastrointestinal discomfort with orlistat and GLP-1 receptor agonists, and potential dependency with phentermine, necessitate tailored treatment approaches. This review highlights the importance of integrating pharmacotherapy with lifestyle interventions to achieve sustainable weight management and identifies areas for future research to optimize therapeutic outcomes for individuals with obesity.