The European Medicines Agency’s (EMA) safety committee (PRAC) has determined that NAION, a rare eye disease, is a very rare side effect of semaglutide, and this risk should be included in the drug’s package leaflet. Semaglutide is the active ingredient in drugs like Ozempic, Wegovy, and Rybelsus, all produced by Novo Nordisk.

The Danish Medicines Agency stated that if symptoms of NAION occur, treatment with semaglutide should be stopped. NAION affects the optic nerve and can cause sudden vision loss in one or both eyes.

The Committee for Medicinal Products for Human Use (CHMP) will now consider PRAC’s assessment. If CHMP agrees, it will recommend the EU Commission update the package leaflet, which would make the final decision. Both PRAC and CHMP are part of the EMA.

Concerns about the potential side effect were raised in two Danish studies from the University of Southern Denmark, prompting the Danish Medicines Agency to request PRAC’s investigation. Known risk factors for NAION include diabetes, high blood pressure, high cholesterol, and severe obesity, especially in combination with type 2 diabetes, making it difficult to determine the cause of NAION cases.

As of May 2025, the Danish Medicines Agency has received 28 reports of NAION from Danish patients treated with semaglutide; 15 patients received Wegovy, 13 received Ozempic, and one patient received both Ozempic and Rybelsus. The first reports of the eye disease from Danish patients treated with semaglutide came in the summer of 2024.