Diabetes, obesity, and bipolar disorder frequently occur together and may share some underlying biological mechanisms. According to the latest World Health Organization estimates, about one in 200 people worldwide, or roughly 37 million people, live with bipolar disorder.

GLP-1 medications are already established treatments for diabetes and obesity, but their possible effects on bipolar disorder have remained unclear.

Large Study Examines GLP-1 Drugs and Bipolar Disorder

To investigate the connection, researchers led by Professor Mark Taylor from Griffith's School of Medicine and Dentistry analyzed nationwide Swedish data from nearly 15,000 people with bipolar disorder who had been prescribed GLP-1 medications over a 15-year period.

"People with bipolar disorder who were taking semaglutide (otherwise known as Ozempic or Wegovy), a type of GLP-1 medication, had significantly lower rates of psychiatric hospitalization compared with periods when they were not taking GLP-1 medicines," Professor Taylor said.

"The findings add to growing evidence that GLP-1 receptor agonists may have benefits beyond diabetes and obesity treatment, and could represent a promising new avenue for bipolar research."

The researchers found that semaglutide use was associated with a 21 percent lower risk of psychiatric hospitalization.

Semaglutide May Affect Brain-Related Processes

The findings suggest that GLP-1 signaling could help protect the brain by reducing inflammation, cellular stress, and other biological processes associated with bipolar disorder.

These effects could potentially contribute to greater mood stability and a lower risk of relapse.

However, the same pattern was not seen with every GLP-1 medication. Liraglutide and dulaglutide were not associated with a reduced risk of psychiatric hospitalization, indicating that any potential mental health benefit may not extend across the entire drug class.

Professor Taylor said he hopes the findings will now be examined in a randomized controlled trial, which would provide stronger evidence about whether semaglutide itself can improve psychiatric outcomes in people with bipolar disorder.

The paper 'Use of glucagon-like peptide 1 receptor agonists and the associated risk of hospitalisation in bipolar disorder, from a nationwide cohort, 2009-2024' has been published in Acta Psychiatrica Scandinavica.