Jens Asbjørn Bøgen
Millions of Americans now fill monthly prescriptions for weight-loss and diabetes injections once hyped as near-miracle drugs.
Federal regulators spent more than a year sifting through clinical-trial data on the entire class of GLP-1 medications, trying to settle whether a rare but devastating eye condition flagged by European reviewers belonged on the American safety profile too.
On Monday, the Food and Drug Administration told manufacturers the answer is yes.
The agency is requiring every GLP-1 receptor agonist to add a new warning about non-arteritic anterior ischemic optic neuropathy, or NAION, a sudden form of vision loss with no known treatment.
The labeling change covers semaglutide (Ozempic, Rybelsus and Wegovy), tirzepatide (Mounjaro and Zepbound), dulaglutide (Trulicity), liraglutide (Victoza and Saxenda), exenatide and the new oral drug orforglipron (Foundayo), which won approval earlier in 2026.
What the agency actually found
The FDA based its decision on a meta-analysis of 126 randomized clinical trials covering 134,253 patients, roughly 78,000 of whom received a GLP-1. The trials identified 15 probable NAION events in total.
Translated to population rates, that worked out to 6.4 cases per 100,000 person-years among GLP-1 users, versus 3.8 per 100,000 among comparators receiving placebo or other glucose-lowering drugs.
Observational data pointed in the same direction. Real-world rates ran closer to 30 per 100,000 person-years, with GLP-1 users showing a higher risk than people on DPP-4 inhibitors (hazard ratio 1.43). The FDA acknowledged limits in the underlying evidence, including the small number of trial events.
NAION itself is described by the FDA as a rare condition that causes acute, painless, decreased vision in one eye, sometimes permanently. It is also associated with diabetes, smoking and high blood pressure, factors common in the same patient population now taking these drugs.
Europe reached the same conclusion first
European regulators moved on the same signal more than a year ago. The European Medicines Agency’s Pharmacovigilance Risk Assessment Committee concluded in June 2025 that NAION is a “very rare” side effect of semaglutide, defined as affecting fewer than 1 in 10,000 patients, drawing partly on two large Danish register-based studies. The Danish Medicines Agency reported 28 national cases at the time of the PRAC decision, rising to 32 by October 2025.
US ophthalmology groups have taken a more cautious line than Europe’s regulators. In a May 2026 consensus statement, the North American Neuro-Ophthalmology Society and the American Academy of Ophthalmology estimated the elevation in relative risk at roughly two-fold but stopped short of advising patients to stop therapy, warning that discontinuation “could pose significant health risks for some patients.”
What patients should watch for
The FDA is telling clinicians to instruct patients to immediately report any sudden, painless loss of vision, new blind spots, distorted colors or blurry central vision in one eye. Anyone experiencing these symptoms should seek same-day evaluation by an ophthalmologist and bring a list of current medications, including any GLP-1.
