Semaglutide, a glucagon-like peptide-1 receptor agonist (GLP-1RA), has transformed the treatment landscape for type 2 diabetes and obesity due to its robust efficacy and wide-ranging therapeutic benefits. This review outlines semaglutide's diverse mechanisms of action, including its roles in glucose homeostasis, weight reduction, and cardiovascular protection. Data from the SUSTAIN and PIONEER clinical trials demonstrate significant reductions in HbA1c, body weight, and major adverse cardiovascular events (MACE), firmly establishing semaglutide as a key agent in diabetes management. The STEP trials further highlight its exceptional effectiveness in weight control, with participants achieving up to 20% weight loss alongside improvements in obesity-related comorbidities. Moreover, ongoing studies such as the FOCUS trial are investigating its impact on microvascular complications. Beyond glycemic control, semaglutide exhibits renoprotective, anti-inflammatory, and potential hepatoprotective effects. Emerging evidence also supports its expanding role in the management of non-alcoholic fatty liver disease (NAFLD), heart failure, polycystic ovary syndrome (PCOS), obstructive sleep apnea (OSA), alcohol use disorder (AUD), and Alzheimer's disease. While gastrointestinal side effects are the most commonly reported adverse events, long-term studies affirm its overall safety and tolerability. The availability of both subcutaneous and oral formulations further enhances treatment adherence and accessibility. As a result, semaglutide has emerged as a cornerstone therapy for a broad spectrum of metabolic, cardiovascular, and neuroendocrine disorders. Future research should continue to explore its therapeutic potential in under-studied populations, including individuals with non-diabetic cardiovascular disease and hepatic fibrosis.
