A study published in the British Journal of Ophthalmology and conducted by researchers at the University of Ottawa analyzed over 30 million reports of adverse events submitted to the Food and Drug Administration (FDA) system between 2017 and 2024 to find that the popular diabetes drug Wegovy (semaglutide) from the Danish pharmaceutical giant Novo Nordisk may be associated with an increased risk of a rare, vision-threatening complication — non-arteritic anterior ischemic optic neuropathy (NAION), or “eye stroke.”
Ischemic optic neuropathy occurs due to disrupted blood supply to the optic nerve and can lead to sudden vision loss. Among all reports related to semaglutide-based medications (approximately 31,000 cases), Wegovy showed the most pronounced association with this complication.
According to the analysis, the likelihood of developing an “eye stroke” was nearly five times higher in individuals using Wegovy compared to those taking another medication with the same active ingredient — Ozempic. The researchers attribute this to the difference in dosages: the maximum dose of Wegovy is 2.4 mg per week compared to 2.0 mg for Ozempic. Furthermore, the risk of developing the complication in men was more than three times higher than in women.
the likelihood of developing an “eye stroke”—specifically non-arteritic anterior ischaemic optic neuropathy (NAION)—was nearly five times higher Ozempic
However, the researchers emphasize that analyzing adverse event databases does not allow for determining the exact frequency of complications and does not prove a direct causal relationship. The results point to a potential risk that requires further prospective studies and more careful monitoring of patients taking medications for obesity treatment.
In 2025, it became known that the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) launched an investigation following numerous complaints about adverse events related to the diabetes and obesity medications Mounjaro, Wegovy, Ozempic, and liraglutide. Hundreds of people reported pancreas problems associated with weight-loss injections.
