Nearly half of adults who began taking semaglutide for obesity stopped treatment within a year, a large Danish study found. Higher rates of discontinuation were observed among adults younger than 30 years, men, and those with histories of using gastrointestinal or psychiatric medication.

The findings, published online on August 28 in JAMA Network Open, add to growing evidence that adherence to GLP-1 medications is a major challenge in the treatment of obesity. Because maintaining weight loss with drugs such as semaglutide may require long-term therapy, understanding which patients are more likely to pause or discontinue could help clinicians provide better counsel and support before and after prescribing.

“The discontinuation rate is considerable; we did not find any subgroup where discontinuation was low,” said lead author Aurélie Mailhac, MSc, of Aarhus University and Aarhus University Hospital in Denmark. “We believe now that the drug needs to be taken long-term, so to increase adherence from the beginning of therapy means personalized support and close follow-up so patients can maintain the therapy.”

In the US, 11% of adults reported currently taking a GLP-1 medication for weight loss in 2026, up from 3% in 2024, according to Gallup. Separately, the Kaiser Family Foundation found in 2025 that 18% of adults had at some point used a GLP-1 for weight loss or another chronic condition.

Mailhac and colleagues set out to understand real-world patterns of adherence to help clinicians identify patients who need additional support to remain on therapy. They conducted a registry-based cohort study of 157,822 adults in Denmark who began using semaglutide for obesity between 2022 and 2024. Participants (median age, 49 years; 69% women) had not previously used the drug and did not have diabetes.

Patients were followed for 1 year, and discontinuation was defined as the end of a patient’s prescription followed by at least 60 days. The study accounted for lower dosing or suboptimal patient adherence.

The researchers also tracked how many patients restarted semaglutide within 3 months and subsequent prescriptions for other medications for obesity management.

Nearly half of patients discontinued semaglutide within a year using the 60-day gap. When researchers used gaps of at least 30 days after discontinuation, the rate rose to 58%.

Stopping treatment was not confined to one patient group: The 12-month risk was at least 41% across every subgroup examined, including categories based on age, sex, income, prior medication use, and obesity-related conditions. However, adults younger than 30 years had a 49% more risk for discontinuation than those aged 45-59 years, and men had a 16% more risk than women.

Patients who had previous bariatric surgery had a lower risk of stopping the drug (risk ratio, 0.89; 95% CI, 0.86-0.93).

Previous use of psychiatric medications was associated with a 13% higher relative risk for discontinuation, while previous gastrointestinal medication use was associated with a 10% greater risk. Those who had taken anxiolytic drugs and antidepressants also had a more risk of stopping the drug.

People with prediabetes, metabolic syndrome, cardiovascular disease, kidney disease, and greater overall comorbidity burden had up to 9% greater risk for discontinuation than those without the conditions.

Discontinuation also did not always represent a permanent end to treatment. Nearly 1 in 4 patients who discontinued semaglutide restarted within 3 months, while 1.4% switched to liraglutide and 0.7% switched to tirzepatide.

The reasons for restarting require further study, including whether patients resumed treatment after regaining weight.

Improving long-term adherence requires clinicians to address treatment expectations and practical barriers at the outset, Mailhac said.

“Discussions about long-term considerations and individualized treatment plans and follow-up around physical activity, medication tolerance, titration, patient expectations, and cost are all important,” she said.

That approach mirrors the experience of Tonia Vinton, MD, internist who specializes in obesity medicine at UT Southwestern Medical Center in Dallas.

“We definitely want to collaborate with our patients to formulate a tailored plan for nutrition, for physical activity, and then also be very careful to monitor their mood and sleep so that we’re looking at this from a comprehensive view on improving their overall health and their metabolic outcomes,” she said.

Clinical support may also address tolerability. Vinton said individualized dose titration and counseling about meal size, timing, and food choices can help patients with gastrointestinal symptoms remain on therapy.

“Unless we’re all really aware of how these meds work and how to counsel patients, unfortunately our patients are going to continue to suffer and struggle,” Vinton said. “Even though we have such a great powerful treatment, if we’re not able to utilize it, it’s not going to be very helpful.”

Various study authors reported receiving grants and personal fees from AbbVie, AstraZeneca, Bristol Myers Squibb, the Norwegian Research Council, the European Research Council, and others.

Kelley Butler is a freelance writer based in the Washington, DC, metropolitan area, covering a range of healthcare topics and trends.