FDA Requires GLP-1 Labels to Warn of Potential NAION Risk as Vision-Loss and Gastroparesis Lawsuits Grow

The FDA is requiring manufacturers of GLP-1 diabetes and weight loss drugs to include a warning for non-arteritic anterior ischemic optic neuropathy (NAION) or sudden vision loss. Eli Lilly and Novo Nordisk are also facing new lawsuits for failing to warn doctors and consumers about the risks associated with their products.

A study published in JAMA Ophthalmology more than two years ago identified a higher likelihood of NAION for patients given semaglutide. There were 17 cases of NAION in the study, published in July 2024, compared to 6 in the control group. The authors noted that the study doesn’t prove causality, but called for additional research.

The FDA said the symptoms of NAION include “sudden, painless vision loss in one eye that patients may notice upon waking; blurred or missing portions of vision (visual defects such as blind spots or tunnel vision); distortion of colors; and reduced central sharpness (e.g., blurry or hazy spots).” The agency adds, “Patients should contact their health care professional right away if they have any of these symptoms,” and “they should talk with their health care professional about whether to continue taking their GLP-1 RA medication or to stop it.”

In a July lawsuit against Novo Nordisk, the manufacturer of Ozempic, the plaintiff’s attorneys accuse the company of attempting to conceal or minimize risks with the drugs, including NAION. The lawsuit says Novo Nordisk “intended to create the impression that these were ‘magic pills’ to help a person lose weight,” but they never disclosed that many people stop taking the drugs because of serious side effects. The lawsuit also states the risk is not worth the potential weight loss reward because the average weight loss is a “modest 10.09% of the person’s body weight” and up to 15% of users fail to achieve any meaningful weight loss.

“A person will need to stay on these drugs for the rest of their lives to maintain the weight loss,” the lawsuit continues. “What is worse is that Defendants kept this information hidden while actively degrading trust in the prevailing view that lifestyle changes like proper nutrition and exercise were the keys to health and can accomplish long-lasting weight-loss and management for most people.”

The FDA references the 2024 JAMA Ophthalmology study, but identified several limitations of the study design. Despite that, the agency determined more research was necessary to determine the potential risk associated with GLP-1s. The FDA conducted an analysis of 126 randomized, controlled clinical trials that showed 6.4 NAION cases per 100,000 person-years in GLP-1 users compared to 3.8 cases in the control group.

The European Medicines Agency (EMA) officially recommended on June 6, 2025, that all semaglutide drugs include a warning about NAION. Another lawsuit against Eli Lilly filed in September 2026 accuses the company of willfully disregarding the known risks and failing to warn consumers in the United States about the higher likelihood of NAION for users of these drugs.

The plaintiff, Donald Tipton, has suffered permanent eyesight loss according to the lawsuit. The attorneys say Eli Lilly updated Mounjaro’s label a dozen times between 2022 and 2025, but still failed to add any warning to health care providers and consumers about known risks of NAION with the product. Novo Nordisk has updated Ozempic’s label at least 13 times since 2017 and also failed to include a NAION warning.

The most common serious side effect that has been associated with GLP-1 drugs is gastroparesis, also known as delayed gastric emptying or “stomach paralysis.” A large 2025 study found an incidence rate of 6.5 per 1,000 person-years for individuals who had obesity, but not type 2 diabetes. The rate of gastroparesis for other obesity treatments was lower, with 2.1 for bupropion-naltrexone and 1.1 for sleeve gastrectomy. Other large observational studies have found a 50-65% higher rate of stomach paralysis for semaglutide users compared to non-users. There are currently over 4,000 pending gastroparesis or gastrointestinal injury federal lawsuits against GLP-1 manufacturers. There are currently over 270 pending NAION cases.

The latest Gallup poll released in July found that 11% of Americans, or about one in nine, currently use GLP-1s for weight loss, while 15% have reported using the drugs for weight loss at some point. In 2024, only 3% of respondents were currently using the drugs at the time of the Gallup poll, and 6% reported using the drugs for weight loss at some point.

Last year, The HighWire reported on HHS Secretary Robert F. Kennedy’s shift in tone regarding GLP-1 medications for weight loss. In November 2025, Kennedy celebrated a significant reduction in prices by the Trump administration and suggested using these drugs as “an arrow in our quiver” to help combat the obesity epidemic. Previously, Kennedy said it would be more effective to provide three meals a day to every man, woman, and child at a fraction of the cost.