SEMAGLUTIDE FOR WEIGHT REDUCTION: A COMPARATIVE ANALYSIS WITH OTHER PHARMACOLOGICAL TREATMENTS

Marta Handzel; Julia Czerniewska; Klaudia Jurkowska; Julia Mądrzak; Olga Endler; Mikołaj Dybicz; Marianna Ciastoń; Magdalena Filuk; Jakub Fidelus; Dominika Dutkiewicz

doi:10.31435/ijitss.2(50).2026.5726

Authors

Marta Handzel Pomeranian Medical University in Szczecin, Szczecin, Poland https://orcid.org/0009-0004-0348-0051
Julia Czerniewska Medical University of Silesia in Katowice, Katowice, Poland https://orcid.org/0009-0009-3769-8047
Klaudia Jurkowska Medical University of Silesia in Katowice, Katowice, Poland https://orcid.org/0009-0003-0205-6999
Julia Mądrzak Faculty of Medicine, Kazimierz Pułaski University of Radom, Radom, Poland https://orcid.org/0009-0007-3387-9225
Olga Endler Faculty of Medicine, Poznan University of Medical Sciences, Poznan, Poland https://orcid.org/0009-0002-0256-9965
Mikołaj Dybicz Faculty of Medicine, Poznan University of Medical Sciences, Poznan, Poland https://orcid.org/0009-0001-7270-7625
Marianna Ciastoń Medical University of Silesia in Katowice, Katowice, Poland https://orcid.org/0009-0001-9458-7097
Magdalena Filuk Collegium Medicum in Bydgoszcz, Bydgoszcz, Kujawsko-Pomorskie, Poland https://orcid.org/0009-0004-6969-7173
Jakub Fidelus Medical University of Lodz, Lodz, Poland https://orcid.org/0009-0006-6889-8509
Dominika Dutkiewicz Independent Public Health Care Centre of the Ministry of the Interior and Administration in Gdańsk, Poland https://orcid.org/0009-0006-2035-8079

DOI:

https://doi.org/10.31435/ijitss.2(50).2026.5726

Keywords:

Semaglutide, Liraglutide, Orlistat, Phentermine, Obesity, GLP-1

Abstract

Obesity is a chronic, complex disease linked to major illness and death. Related conditions include heart disease, type 2 diabetes, and cancer. Its global prevalence has soared, demonstrating the need for treatments beyond lifestyle change. Pharmacotherapy is essential, particularly for people unable to maintain weight loss through behavioural interventions. This review evaluates the efficacy and safety of glucagon-like peptide-1 (GLP-1) receptor agonists, specifically semaglutide and liraglutide. These are assessed against established anti-obesity drugs, including orlistat and phentermine. A structured search was carried out across PubMed, Scopus, and Google Scholar. Priority was given to randomised controlled trials, meta-analyses, and large observational studies published from 2010 to 2025. Key clinical trial programmes, such as STEP, SUSTAIN, LEADER, SELECT, and SURMOUNT, were critically reviewed. Semaglutide shows superior efficacy. Mean weight reductions often exceed 10–15%. These reductions are linked to considerable improvements in glycaemic and cardiometabolic parameters. Liraglutide provides modest weight loss but has proven cardiovascular benefits. Orlistat and phentermine have lower efficacy. They also have tolerability issues and limited long-term use. Despite their strengths, GLP-1 receptor agonists cause gastrointestinal side effects, high cost, and have limited long-term safety data. GLP-1 receptor agonists represent a major advance, making obesity treatment more targeted. Future studies ought to focus on long-term outcomes, accessibility, and improving the tolerability and affordability of therapy.

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