European Medicines Agency Confirms a Notable Increase in NAION Among Users of Ozempic and Wegovy

Semaglutide medications like Ozempic and Wegovy have emerged as powerful tools in managing type 2 diabetes and promoting weight loss. While widely used for their benefits, a serious and often irreversible eye condition called Non-Arteritic Anterior Ischemic Optic Neuropathy (NAION) has recently drawn new scrutiny from European health regulators and consequent attention in America.

In June 2025, the European Medicines Agency (EMA) officially confirmed that NAION is a “very rare” side effect of semaglutide drugs, recommending urgent updates to product labeling and treatment protocols. Here’s what patients and healthcare professionals need to know. If you’ve experienced vision problems or other serious health effects after taking Ozempic or Wegovy, including stomach paralysis, DVT, and others, contact Leandros A. Vrionedes, P.C., to review your situation with a dedicated New York Ozempic injury lawyer.

What the EMA Found and Why It Matters

The EMA’s Pharmacovigilance Risk Assessment Committee (PRAC) completed an exhaustive review of semaglutide, including data from clinical trials, post-marketing surveillance, non-clinical studies, and medical literature, and concluded that NAION is a very rare but real adverse effect of taking semaglutide. It may affect up to one in 10,000 people taking the drug (millions of people are currently taking Ozempic or Wegovy).

Large epidemiological studies consistently showed that adults with type 2 diabetes using semaglutide were approximately twice as likely to develop NAION compared to those not using the drug.

NAION is caused by insufficient blood flow to the optic nerve, often leading to sudden, painless vision loss that is typically permanent. It ranks as the second most common cause of optic nerve-related blindness (after glaucoma) and may happen unexpectedly, sometimes noticed only upon waking.

As a result of these findings, EMA recommended updating semaglutide product information to include NAION as a side effect with “very rare” frequency. The agency also urged doctors and patients to stop semaglutide immediately if NAION is confirmed.

Clinical Evidence Underpinning EMA’s Decision

The decision was driven by both real-world data and clinical evidence. Epidemiological studies examining large populations found a doubling of NAION risk among semaglutide users.

In earlier observational studies from the U.S. and Europe, risk escalated for diabetic patients and even more so for overweight and obese individuals, up to a 7.6-fold increase in NAION risk when semaglutide was used for weight loss.

While clinical trials also showed a slightly increased risk compared to placebo, the relatively small sample sizes limited statistical power. This is why EMA’s use of broad data sources and real-world surveillance made the regulatory finding more robust.

What Patients and Providers Need to Know

The EMA’s update carries real-world implications for both clinicians and patients overseas:

• Updated labeling: Any medical literature or product insert for Ozempic, Wegovy, or Rybelsus in Europe must now include NAION as a “very rare” yet serious side effect.
• Prompt action required: If a patient on semaglutide reports sudden vision loss or rapid impairment, they should immediately contact their physician, and treatment should be discontinued if NAION is confirmed.
• Ongoing surveillance: World health bodies, including the World Health Organization (WHO), have joined EMA in urging vigilance and continued monitoring of NAION risk in semaglutide users.

Regulatory Context and Industry Response

This announcement marks one of the first major drug safety signals emerging from clinical use rather than trial data. It’s notable because NAION is a devastating condition with no known cure, highlighting the ethical imperative for transparent drug safety communication.

Drugmaker Novo Nordisk has responded by arguing that current evidence does not establish definitive causality and that the benefit-risk profile of semaglutide remains favorable. Nevertheless, EMA’s decision represents a significant update in global medical oversight.

What Happens Next in the U.S.?

Currently, the U.S. Food and Drug Administration (FDA) has not issued similar warnings or required label changes. However, U.S. law firms have filed NAION-related lawsuits alleging failure to warn, spurred by the EMA’s review and mounting real-world evidence.

Key Takeaways for Patients

• NAION remains a rare but serious potential risk of semaglutide-based medications.
• EMA’s regulatory actions reinforce the need for immediate medical evaluation if vision symptoms appear.
• Patients need clarity on how NAION differs from other vision concerns like diabetic retinopathy or transient visual symptoms.
• Legal options may exist if patients were not warned about these risks and suffered vision loss.

How Leandros A. Vrionedes, P.C. Can Help

At Leandros A. Vrionedes, P.C., we closely follow advancements in medical research and regulatory updates, especially regarding side effects like NAION that can have lifelong consequences. If you or a loved one experienced vision loss while taking Ozempic or Wegovy, we offer thorough case reviews and can help protect your rights. Contact us today for a free consultation to see whether you may have grounds for a product liability or failure-to-warn claim based on recent EMA revelations and your documented medical experience.