Patients Sue Makers of Weight-Loss Drugs Over Vision Loss Claims

Hundreds of consumers are initiating legal action against manufacturers of popular GLP-1 receptor agonist medications, including Ozempic, Wegovy, Mounjaro, and Zepbound. The lawsuits claim that these drugs may increase the risk of nonarteritic anterior ischemic optic neuropathy (NAION), a rare condition that can lead to sudden vision loss.

NAION, described by the American Academy of Ophthalmology and the National Eye Institute as an "eye stroke," occurs when blood flow to the optic nerve is abruptly reduced, resulting in vision impairment. Dr. Douglas Lazzaro, an ophthalmologist at NYU Langone Health, noted that NAION currently has no available treatment and can cause significant vision loss.

The companies involved, Novo Nordisk and Eli Lilly, have reportedly disputed the allegations. Novo Nordisk has stated that its research shows no increased risk of NAION associated with its drugs, while Eli Lilly maintains that current studies do not prove a causal link between GLP-1 medications and the condition. Fox News Digital has reached out to the companies for comment.

Recent research has focused on semaglutide, one of the active ingredients in Ozempic and Wegovy. A 2025 data analysis published in JAMA Ophthalmology found a modest increase in NAION risk among semaglutide users compared to those taking SGLT2 inhibitors. Another study from Harvard Medical School in 2024 indicated that patients with type 2 diabetes prescribed semaglutide had a roughly fourfold higher relative risk of developing NAION, though the absolute risk remained very low. The authors of both studies cautioned that their findings were observational and could not definitively prove causation, emphasizing the need for more research.

The U.S. Food and Drug Administration (FDA) is reviewing available evidence concerning a potential association between semaglutide and NAION but has not yet concluded that the drug causes the condition or issued a safety warning. In Europe, however, the European Medicines Agency has recommended adding NAION as a "very rare" adverse reaction to semaglutide product information.

Lazzaro acknowledged the complexity of assessing statistical significance due to confounding variables such as patient obesity levels, age, sex, and pre-existing conditions like hypertension. However, he noted that after attempting to control for these factors, studies still indicated a higher risk of NAION. "My overall take on the matter is there's probably a slightly increased risk of NAION when using the semaglutides, but I think the health benefits outweigh the risks," Lazzaro stated, adding that he would likely recommend the drugs unless a patient presented with specific optic nerve characteristics that put them at higher risk.

NAION typically manifests as sudden, painless vision loss in one eye, often noticed upon waking. Other symptoms can include blurred or dimmed vision and loss of peripheral or color vision. Key risk factors for NAION include age, diabetes, high blood pressure, high cholesterol, obstructive sleep apnea, and smoking. Experts note that since many individuals taking GLP-1 medications have underlying conditions like diabetes or obesity, these pre-existing factors could also contribute to vision issues.

While vision loss from NAION is often permanent with no proven treatment to reverse optic nerve damage, healthcare providers emphasize that patients should consult their doctor before discontinuing prescribed GLP-1 medications. For many individuals managing diabetes or obesity, the proven health benefits of these drugs may outweigh the potential vision risks.