A Rutgers study found three to four additional cases of ischaemic optic neuropathy per 10,000 patients taking GLP-1 medicines over 18 months, but researchers say the association does not prove the drugs are the cause.
Researchers at Rutgers University have found a possible link between popular diabetes and weight-loss drugs and a rare eye disorder that can cause sudden vision loss, adding to a growing body of safety concerns around semaglutide-based medicines such as Ozempic and Wegovy. The study, published in Annals of Internal Medicine, examined adults aged 18 to 65 with type 2 diabetes and found a modestly higher risk of ischaemic optic neuropathy among patients who had recently started taking glucagon-like peptide-1, or GLP-1, medicines.
Ischaemic optic neuropathy occurs when blood flow to the optic nerve is reduced, depriving the nerve of oxygen and nutrients it needs to transmit visual information from the eye to the brain. In the most common form, non-arteritic anterior ischaemic optic neuropathy, people may experience sudden blurring, dimming or loss of part of their vision in one eye. The damage is often permanent, although some recovery can occur, usually in the first six months, according to the Rutgers team.
Chintan Dave, a core faculty member at the Rutgers Institute for Health, Health Care Policy and Aging Research, said the increase in risk was small, amounting to about three to four extra cases per 10,000 patients treated with GLP-1 drugs over 18 months. Dave said the finding mattered because the condition can cause sudden, potentially lasting vision loss, and stressed that clinicians and patients should be alert to symptoms that warrant urgent eye assessment.
The study does not prove that the medicines directly cause the problem, and the authors said other health differences between patients could help explain the association. Even so, the results come after a series of regulatory warnings. In June 2025, the World Health Organisation issued an alert over a very rare risk of non-arteritic anterior ischaemic optic neuropathy with semaglutide medicines, citing reports from several countries. In February 2026, the UK’s Medicines and Healthcare products Regulatory Agency also warned that sudden loss of vision while taking semaglutide drugs should prompt urgent ophthalmological evaluation, and that treatment should be stopped if NAION is confirmed.
The new Rutgers findings are likely to intensify scrutiny of GLP-1 medicines, which have become widely used not only for type 2 diabetes but also for weight management and, in some cases, cardiovascular risk reduction. The researchers noted that cases of ischaemic optic neuropathy were more common among men and among adults aged 50 to 65 in their study. They said the key public-health message was not to alarm patients, but to ensure sudden vision changes are taken seriously and assessed quickly, especially in people who may already be at higher risk.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
