A new analysis of global drug safety reports suggests that the weight-loss medication Wegovy may be linked to higher reporting rates of a rare condition that can cause sudden vision loss.
Researchers analyzing data from the U.S. Food and Drug Administration’s Adverse Event Reporting System found that Wegovy had the strongest association with reports of ischemic optic neuropathy, sometimes called an “eye stroke,” among several drugs in the same class.
The findings were published in the British Journal of Ophthalmology and are based on an analysis of more than 30 million adverse event reports submitted to the FDA between 2017 and 2024.
Ischemic optic neuropathy occurs when blood flow to the optic nerve is reduced or interrupted. The condition can lead to sudden vision loss in one or both eyes. While rare, it has recently been discussed as a possible complication associated with medications in the GLP-1 receptor agonist family.
These drugs include semaglutide medications such as Wegovy, Ozempic and Rybelsus, as well as tirzepatide drugs such as Mounjaro and Zepbound. They are widely prescribed for type 2 diabetes and obesity and have become increasingly common treatments for weight management.
To explore whether specific drugs might be linked to different risks, the researchers examined reports of unintended side effects submitted to the FDA database. Among more than 30 million reports, 31,774 involved semaglutide medications.
Within that group, the analysis identified 28 reports of ischemic optic neuropathy associated with Wegovy and 47 reports associated with Ozempic. Because Ozempic has been available longer and is used more widely, it generated many more overall reports of side effects.
After adjusting for reporting patterns, the researchers found that Wegovy showed the strongest statistical signal for ischemic optic neuropathy. The odds of reports of the condition were nearly five times higher for Wegovy than for Ozempic in the database analysis.
The analysis also suggested that men had higher reporting odds than women. When the data were broken down by sex, the strongest signal appeared among men using Wegovy.
Researchers caution that the FDA reporting system cannot determine whether a drug actually caused a reported side effect. The database relies on voluntary reports from clinicians, manufacturers and patients, and it does not provide information on how many people took the drug overall.
Because of this, the analysis cannot determine how common the condition is among people taking GLP-1 medications.
Media attention may also influence reporting patterns, the authors noted, and the database does not include detailed medical histories that could help explain why a person experienced the event.
Still, the researchers say the findings highlight a potential safety signal that deserves closer study.
“This study provides the first evidence of a formulation-and dose-dependent ION risk, with the strongest association observed for Wegovy,” the researchers wrote.
They suggest that differences in drug dose, route of administration and prescribing patterns may help explain the signal. Wegovy uses a higher dose of semaglutide than Ozempic and is specifically prescribed for obesity.
The authors speculate that the drug’s effects on blood pressure, fluid balance and circulation could potentially contribute to reduced blood flow to the optic nerve, though no direct clinical mechanism has been confirmed.
Experts say further research will be needed to determine whether a true causal link exists.
GLP-1 medications have gained significant attention in recent years because of their ability to promote weight loss and improve blood sugar control. Studies have also found benefits for cardiovascular health in some patients.
As use of these medications expands, researchers say ongoing monitoring of rare side effects will remain important.
The study analyzed reports submitted to the U.S. Food and Drug Administration’s Adverse Event Reporting System (FAERS), a global database used to monitor potential medication side effects. The research was published in the peer-reviewed journal British Journal of Ophthalmology.