Introduction

Pharmacologic therapy is a key component of obesity management, either as standalone treatment or in conjunction with procedural interventions. The role of weight loss medications in the peri-ESG period remains unclear, with questions surrounding whether ESG reduces the need for pharmacotherapy or serves as a platform for combination therapy. Limited data exist on how prescribing patterns evolve before and after ESG in real-world settings. This study aims to evaluate the use of anti-obesity medications before and after ESG, focusing on patterns of pharmacologic initiation and its relationship to weight loss outcomes.

Aims & Methods

We conducted a retrospective review of 236 patients who underwent ESG at Singapore General Hospital between November 2020 and December 2025. All procedures were performed by a single experienced endoscopist using a U-shaped suturing pattern. For this analysis, we examined the use of anti-obesity medications before and after the ESG. Medications included GLP-1 receptor agonists, sympathomimetic agents, lipase inhibitors, and combination therapies. The primary outcome was the proportion of patients receiving pharmacotherapy across timepoints and its association with total body weight loss (%TBWL).

Results

Among the 236 ESG patients, 21.6% had previously used anti-obesity medications, most commonly GLP-1 receptor agonists or phentermine. This group consistently achieved the lowest total body weight loss (%TBWL) across all follow-up points. Compared to medication-naïve patients, their mean %TBWL was significantly lower at 6 months (9.9% vs 17.2%, p = 0.015), 12 months (7.8% vs 13.8%, p = 0.026), and 24 months (4.3% vs 10.6%, p = 0.003). These findings underscore the complexity of obesity care, as even patients exposed to multiple treatment modalities may continue to experience suboptimal outcomes.
After ESG, 37.7% of patients were initiated on pharmacotherapy, most commonly semaglutide (n = 66), including 38 on subcutaneous and 28 on oral formulations, with estimated mean doses of 1.63 mg/week and 13.2 mg/day, respectively. Phentermine and liraglutide were used in 13.9% and 3.0% of patients. Patients who received medications only after ESG had lower %TBWL at 6 months compared to those never on medications (14.0% vs 18.8%, p = 0.027), but outcomes were similar by 12 and 24 months. This suggests that pharmacotherapy may help support suboptimal early responders and mitigate longer-term differences.

Conclusion

Anti-obesity medications, particularly semaglutide, are commonly introduced after ESG to support patients with suboptimal early weight loss. While those requiring pharmacotherapy initially experienced less %TBWL, outcomes equalized by 12 months, suggesting a role for adjunctive treatment in slower responders. Patients who had previously used weight loss medications consistently achieved poorer outcomes, highlighting the challenges of obesity management even with multimodal therapy. These findings underscore the importance of individualized treatment strategies and the complementary role of pharmacotherapy alongside ESG in real-world practice.

Disclosure

​NIL