PRAC assesses that NAION could be a very rare side effect of Ozempic, Rybelsus and Wegovy
Updates of 2 October 2025
- The product information for Rybelsus, Ozempic and Wegovy available on EMA’s website was updated on 30 September. NAION (non-arteritic anterior ischemic optic neuropathy) has been included as a possible very rare side effect of these medicines.
- Since May, the Danish Medicines Agency has received 4 more reports of NAION, bringing the total of Danish reports to 32. 14 of these reports relate to Ozempic, 17 to Wegovy, and 1 to a patient treated with both Ozempic and Rybelsus.
EMA’s Pharmacovigilance Risk Assessment Committee (PRAC) recommends that the product information for semaglutide medicines should include information that the rare eye condition NAION could be a very rare side effect. Treatment should be stopped if symptoms of NAION occur.
Based on a concern raised in two major Danish register-based studies, among others, PRAC has investigated in a separate procedure the risk that NAION may be a possible side effect of semaglutide medicines. NAION is a rare eye condition which affects the optic nerve, causing a sudden complete or partial loss of vision in one eye or, more rarely, both eyes.
PRAC has reviewed all available data on NAION with semaglutide, including data from pre-clinical studies, post-marketing surveillance and the medical literature. Based on its review, PRAC has concluded that NAION is a very rare side effect of semaglutide, and that the risk should be included in the side effect sections of the product information (package leaflet and summary of product characteristics). The frequency of ‘very rare’ means the side effect may be expected to affect less than 1 in 10,000 people.
The recommendation applies to both diabetes and weight-loss medicines that contain semaglutide, i.e. the diabetes medicines Ozempic and Rybelsus and the weight-loss medicine Wegovy.
EMA’s Committee for Medicinal Products for Human Use (CHMP) is now going to consider the assessment by PRAC.
See a doctor if loss of vision occurs
Some of the known risk factors for NAION include diabetes, high blood pressure, elevated cholesterol levels and severe overweight, especially in combination with type 2 diabetes. That is why patients in the target groups for diabetes and weight-loss medicines are particularly predisposed to NAION, and it may be difficult to determine if NAION cases are caused by the medicine or other health-related causes.
No matter what, it is important to see a doctor immediately if you get symptoms of NAION when on semaglutide medicines.
“If you experience a sudden loss of vision or rapidly worsening eyesight, you should see your doctor immediately to have it checked. If NAION is confirmed, you should stop taking the medicine and switch to another treatment”, says Line Michan, Head of Division at the Danish Medicines Agency.
She also asks people to report symptoms of NAION to the Danish Medicines Agency if it is suspected to be a side effect of the medicine. You can do so on this webpage: Report a side effect from medicines.
28 Danish reports on NAION
As of 31 May 2025, the Danish Medicines Agency has received 28 reports about NAION from Danish patients treated with a semaglutide medicine. The reports include 15 people treated with Wegovy and 13 people treated with Ozempic, one of whom received both Ozempic and Rybelsus.
“We’ve been alert to the possibility that NAION could be a possible side effect of semaglutide medicines since receiving the first reports of the eye condition in Danish patients in the summer of 2024. When the two Danish register-based studies were published, we encouraged PRAC to initiate a separate review to investigate this safety signal,” says Line Michan.
Read more:
Questions and answers on weight-loss medicines and diabetes medicines (in Danish only).