Ozempic NAION Side Effects Result in Vision Loss Warnings by European Regulators

European regulators are requiring new information that warns about the potential link between Ozempic and NAION, which can cause sudden vision loss due to reduced blood flow to the optic nerve head.

An investigation by European regulators has determined that the side effects of Ozempic, Wegovy and Rybelsus, which all use the same active ingredient semaglutide, could cause about one out of every 10,000 users to experience sudden loss of vision or blindness, resulting in recommendations that new warnings be added to the product information.

The European Medicines Agency (EMA) Pharmacovigilance Risk Assessment Committee (PRAC) issued a press release on June 6, announcing that its investigators have confirmed a link between the Novo Nordisk diabetes and weight loss drugs, and a risk of developing non-arteritic anterior ischemic optic neuropathy (NAION).

Ozempic (semaglutide) is the most widely used medication containing semaglutide, which was approved as a treatment for type 2 diabetes in 2017. Rybelus, which contains semaglutide in tablet form, was approved two years later. As the medications gained popularity for weight loss, Novo Nordisk then introduced a diet drug version of semaglutide, which is sold under the brand name Wegovy.

The medications are all part of a popular new class of drugs, known as glucagon-like peptide-1 (GLP-1) receptor agonists, which also include Eli Lilly medications like Mounjaro and Zepbound.

As more users receive the drugs, a steady stream of new concerns have emerged about potential side effects GLP-1 medications. Most of those concerns have centered on gastrointestinal problems linked to the medications, such as stomach paralysis and intestinal obstruction, which has led to a growing number of Ozempic lawsuits, Wegovy lawsuits and Mounjaro lawsuits filed in courts nationwide over the past few years.

However, concerns about Ozempic vision loss problems began to emerge in July 2024, following the publication of a study by Harvard researchers who found that patients using semaglutide may face a seven-fold increased risk for experiencing sudden vision changes, blurred sight, blindness or other symptoms linked to NAION, a rare condition where the optic nerve suffers from insufficient blood flow. As a result, a number of Ozempic NAION lawsuits have since been filed as a result by patients who say they suffered vision loss due to the drugs’ side effects.

In January 2025, another study was published in medRxiv, which led the Danish Medicines Agency to officially request an investigation into Ozempic NAION risks by the European Pharmacovigilance Risk Assessment Committee.

PRAC’s press release indicates that the agency has analyzed data on semaglutide NAION cases from studies, clinical trials and post-market surveillance, determining that it is a rare side effect of the drug that may affect up to one in 10,000 users.

“Results from several large epidemiological studies suggest that exposure to semaglutide in adults with type 2 diabetes is associated with an approximately two-fold increase in the risk of developing NAION compared with people not taking the medicine,” the press release states. “EMA has therefore recommended that the product information for semaglutide medicines is updated to include NAION as a side effect with a frequency of ‘very rare’. If patients experience a sudden loss of vision or rapidly worsening eyesight during treatment with semaglutide, they should contact their doctor without delay.”

The European regulators also noted that if doctors confirm a NAION diagnosis, use of Ozempic, Wegovy or Rybelsus should be halted immediately.

The process now requires that the PRAC send its recommendations and assessment to the Committee for Medicinal Products for Human Use (CHMP), which will likely adopt PRAC’s opinion. At that point the issue will be sent to the full European Commission, which will issue a legally binding decision on how to respond to, and warn of, the risks across the entirety of the European Union.

Ozempic Side Effects Lawsuits

There are currently more than 1,800 GLP-1 lawsuits already pending throughout the U.S. federal court system, which have been centralized in the Eastern District of Pennsylvania under U.S. District Judge Karen Marston, as part of a multidistrict litigation (MDL).

However, that litigation is almost entirely focused on the gastrointestinal side effects of the drugs, and not vision problems.

To help test how juries may respond to certain evidence and testimony that will be central throughout thousands of individual claims, Judge Marston is presiding over coordinated discovery and pretrial proceedings to prepare a small group of cases for early trial dates.

While the outcomes of these early test cases will not be binding on other claims, they will be closely watched and may help the parties negotiate GLP-1 settlements to resolve large numbers of lawsuits in the future.

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