Semaglutide tied to fewer asthma attacks in large UK records study

People with asthma or COPD who started GLP-1 drugs had fewer respiratory flare-ups than similar patients who started a different class of diabetes medicine, according to research presented September 8, 2026 at the European Respiratory Society (ERS) Congress in Barcelona ^[1][2].

The effect was largest for semaglutide, sold as Ozempic and Wegovy, which was linked to roughly a 38% reduction in asthma exacerbations and about a 21% reduction in COPD exacerbations ^[2]. The ERS press release describes the asthma figure as nearly 40% and the COPD figure as 20% ^[1].

The work was led by Chloe Bloom, a clinical associate professor in respiratory epidemiology at the National Heart & Lung Institute, Imperial College London, and presented by Bohee Lee ^[1]. It analyzed UK electronic medical records using four parallel studies, each covering between 20,000 and 22,000 people who started a GLP-1 drug or a sulfonylurea, another type of diabetes medicine ^[1]. From more than 1.1 million adults with asthma or COPD, the researchers built a new-user cohort of 8,266 people starting GLP-1 drugs and 20,273 starting sulfonylureas, and compared the groups using weighted propensity scoring ^[2].

Across all GLP-1 drugs, the study found a 14% lower risk of an asthma or COPD exacerbation compared with sulfonylurea users ^[2]. An exacerbation was defined as a short course of oral steroids, an emergency department visit, a hospitalization, or death ^[2]. The association varied by drug: exenatide (Byetta, Bydureon) was tied to a 23% reduction, dulaglutide (Trulicity) to 12%, and semaglutide to 30% overall ^[2]. Liraglutide (Victoza, Saxenda) and lixisenatide (Adlyxin) showed no change ^[2].

The results did not appear to be explained by metabolic factors. Semaglutide's effects were not modified by baseline body mass index, HbA1c, insulin resistance, weight change during treatment, or change in blood sugar control, Bloom reported ^[2]. Exacerbations also did not appear to be modified by age, smoking, or eosinophil count ^[2]. "Metabolic factors did not appear to significantly influence effects, supporting the possibility of direct pulmonary mechanisms," Bloom said ^[2].

Bloom said previous research suggests GLP-1 receptor agonists may have anti-inflammatory effects, but that asthma and COPD outcomes have not been included as outcomes in GLP-1 drug trials ^[1].

Experts urge caution

Bloom said the findings "should not change treatment decisions on their own" and that people with asthma or COPD "should not start GLP-1 receptor agonists specifically for their lung condition outside current prescribing guidance" ^[1][2].

Alexander Mathioudakis of the University of Manchester, who was not involved in the research, called it one of the largest real-world studies of GLP-1 drugs and airways disease and one of the first to look at whether effects differ between individual GLP-1 drugs ^[1][2]. He said clinical trials including respiratory outcomes are needed ^[1][2].

Marie Spreckley of the University of Cambridge said it "is too early to state that semaglutide reduces or prevents asthma attacks," and that people should not seek semaglutide specifically for asthma or change their existing asthma treatment because of these findings ^[2]. Stephen Burgess, also of Cambridge, said it is not clear whether the semaglutide finding and the lack of findings for similar drugs reflect a true drug-specific effect or a chance finding, and that it may simply be that more data exists for semaglutide ^[2].

The study was supported by Asthma+Lung UK, and Bloom reported no personal disclosures ^[2].

Why it matters for patients

The study is observational, meaning it can show an association but not that GLP-1 drugs caused the reduction in attacks ^[2]. Patients were prescribed these drugs for a condition such as type 2 diabetes, not for asthma or COPD ^[1][2]. No GLP-1 drug is approved in the US to treat asthma or COPD, and the researchers say these results do not justify starting one for that purpose ^[1][2].

The practical question the data speak to is narrower: for people who already qualify for a GLP-1 drug because of type 2 diabetes or obesity and who also have asthma or COPD, these treatments may carry additional respiratory benefits ^[1]. Bloom said the results are encouraging but need confirmation in trials ^[1].

Nothing in the findings suggests changing inhalers, steroids, or other asthma or COPD treatment ^[2]. The study also did not report on side effects, cost, or insurance coverage for this use.

What happens next

Mathioudakis and Bloom both called for randomized trials that include respiratory outcomes such as asthma attacks, COPD exacerbations, lung function, symptoms, and quality of life ^[1][2]. No specific trials, start dates, or results timelines have been reported.