GLP-1 RAs for IBD & Obesity: Weight Loss & Metabolic Benefits – A Review

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs), medications initially developed for type 2 diabetes and obesity, are showing promise as a potential treatment option for adults with inflammatory bowel disease (IBD) who also experience metabolic issues. A recent systematic review suggests these drugs may offer a safe and effective way to manage weight and improve metabolic health in this patient population, without necessarily worsening IBD symptoms.

The findings, published in Alimentary Pharmacology & Therapeutics, analyzed data from multiple studies, primarily observational, and indicated that GLP-1 RA use was associated with meaningful weight loss and metabolic improvements without a clear increase in IBD flares. Here’s particularly relevant as obesity is increasingly recognized as a factor that can worsen outcomes for individuals with IBD, potentially leading to more frequent hospitalizations, a greater need for surgery, and difficulty achieving remission.

“The use of GLP-1 RAs in gastroenterology is rapidly expanding, including among patients with IBD who were excluded from pivotal GLP-1 trials,” explains Dr. Joëlle St-Pierre, clinical assistant professor in the Division of Gastroenterology and Hepatology at the University of Calgary, Canada, and senior investigator of the study. “As clinicians increasingly encounter patients with IBD as well as obesity, diabetes, or metabolic liver disease, there is a clear need to synthesize what is known about safety, metabolic effects, and IBD-specific outcomes to support evidence-informed clinical decision-making.”

The systematic review included 14 studies, encompassing a wide range of participants – from small clinical cohorts to large administrative registries with over 61,000 individuals. Follow-up periods ranged from three months to seven years. Researchers focused on weight changes, metabolic markers, IBD disease activity, and safety outcomes.

Across the studies, consistent weight loss was observed following the initiation of GLP-1 RA therapy. Weight loss generally ranged from approximately 4% to over 11% of total body weight over periods of three to fifteen months, with a significant proportion of patients – between 58% and 67% – achieving at least a 5% reduction in total body weight. Comparisons between IBD patients and those without IBD receiving GLP-1 RAs showed broadly similar weight loss outcomes. One study specifically evaluating tirzepatide showed a greater mean weight reduction in IBD patients receiving a 15-mg dose compared to non-IBD controls (-26 lb vs -21 lb; P=.002).

Beyond weight loss, the review also identified improvements in metabolic markers. Two studies reported significant improvements in glycemic control, with a median reduction in hemoglobin A1C levels. Another study showed a mean A1C decrease of −0.76% (95% confidence interval, −0.99 to −0.52) among patients with IBD treated with tirzepatide. Lipid outcomes were more variable, with some studies showing modest improvements in cholesterol and triglyceride levels, while others did not find statistically significant changes.

Importantly, the review found no evidence that GLP-1 RA exposure increased IBD disease activity. Smaller clinical studies reported stable clinical indices and inflammatory biomarkers, such as C-reactive protein (CRP) and fecal calprotectin, following treatment initiation. Larger analyses of administrative data suggested a lower risk of corticosteroid use (hazard ratios ranging from 0.54 to 0.66), hospitalization (hazard ratios 0.73–0.74), and IBD-related surgery among patients using GLP-1 RAs.

However, Dr. St-Pierre cautions that the associations observed in these observational studies should be interpreted carefully, particularly given the reliance on administrative data and surrogate endpoints. “While some observational studies suggest associations with improved IBD-related outcomes, these findings should be interpreted cautiously given reliance on administrative data and surrogate end points.”

The safety profile of GLP-1 RAs in IBD patients appears to be consistent with that observed in the general population. Adverse events were primarily gastrointestinal, including nausea, diarrhea, constipation, and abdominal pain, with frequencies comparable to those reported in individuals without IBD. Discontinuation rates ranged from 11% to 24%, most often due to gastrointestinal intolerance. Large registry-based studies found no increased risk of serious adverse events such as ileus, intestinal obstruction, pancreatitis, or gallbladder disease.

“the available data are reassuring,” Dr. St-Pierre states. “GLP-1 RAs appear to be generally well tolerated in patients with IBD, with gastrointestinal adverse effects similar to those seen in non-IBD populations. Importantly, there was no consistent signal for increased disease flares or therapy escalation.”

The researchers suggest that these findings support the cautious use of GLP-1 RAs in selected IBD patients who are prescribed these medications for approved metabolic indications, with appropriate counseling and monitoring. However, they also emphasize the need for further research, particularly prospective, IBD-specific studies that incorporate objective inflammatory measures and detailed metabolic phenotyping. Future research should also consider the effects of GLP-1 RAs on body composition in IBD patients, who often exhibit altered muscle and adipose tissue distribution compared to the general population.

According to a study published in November 8, 2025, patients with IBD and obesity using GLP1-RAs were able to achieve significant weight loss and had lower risks of surgery and hospitalizations. Semaglutide, liraglutide, and tirzepatide resulted in weight loss of -9.6 kg, -9.4 kg, and -11.8 kg respectively after 3 months of follow-up.