FDA Tells Ozempic, Wegovy and Zepbound Makers to Warn of Rare Vision Loss

The Food and Drug Administration told manufacturers of GLP-1 medications to update their prescribing labels with a warning about non-arteritic anterior ischemic optic neuropathy, or NAION, Reuters reported. The directive landed Nov. 9, 2026, and targets the warnings and precautions section of the labels. It covers the entire class of drugs with GLP-1 receptor agonist activity — semaglutide, the ingredient in Ozempic and Wegovy, tirzepatide, the ingredient in Mounjaro and Zepbound, plus Trulicity, Victoza, Saxenda and Rybelsus.

The agency's review pulled together 126 randomized clinical trials covering 134,253 people. It found 10 possible NAION cases among GLP-1 users and 5 in the comparison groups, according to the FDA. The reported rate was 6.4 cases per 100,000 person-years for GLP-1 users, while the placebo and other blood-sugar medication group came in at 3.8 cases per 100,000 person-years. A separate 2025 study in JAMA Network Open compared two matched groups of 79,699 patients with type 2 diabetes each and reported a higher risk over two years — though its authors stressed the observational design could show an association, not causation.

Eli Lilly said it is reviewing the FDA's update and will respond to the agency. Novo Nordisk said the available data does not establish a causal link and stood behind the benefit-risk profile of its medicines, per Reuters.

NAION happens when blood flow to the front of the optic nerve falls short, injuring the fibers that carry signals from the eye to the brain. It's nicknamed an eye stroke, and it can bring abrupt, painless vision loss in one eye with no guaranteed cure. Blavity Health medical reviewer Dr. Justus Rabach pointed out the FDA's own real-world analysis cut both ways: no statistically significant increase against SGLT-2 diabetes medicines, but an increased risk against DPP-4 medicines. In 2025, the European Medicines Agency listed NAION as a very rare side effect of semaglutide, potentially affecting up to one in 10,000 users.

Warning signs include sudden painless vision loss in one eye, blurred or hazy vision, blind spots, tunnel vision, faded colors and reduced central sharpness. The FDA flagged diabetes, high blood pressure, smoking, sleep apnea, anemia and kidney disease as risk factors — many of which already overlap with the patients taking these drugs, making the link harder to untangle. Neuro-ophthalmologist Larry Frohman, of Rutgers New Jersey Medical School and the North American Neuro-Ophthalmology Society, said in a statement published by the American Academy of Ophthalmology: 'If you notice sudden, painless vision loss, see an ophthalmologist promptly.'

The FDA stopped short of telling patients to quit. It recommends a conversation about discontinuing the drug once a doctor confirms NAION, and it says nobody should stop or adjust a prescription on their own. Updated medication guides and prescribing information will show up at pharmacies in the coming months, while regulators and researchers keep tracking post-marketing data to sort how much of the risk belongs to the drugs and how much to conditions like diabetes and hypertension.