FDA adds vision-loss warning to Ozempic, Zepbound and other GLP-1 drugs

What NAION is: The FDA describes NAION as a rare condition caused by reduced blood flow to the front of the optic nerve. It typically causes sudden, painless vision loss in one eye, often noticed on waking, along with blind spots, blurry or hazy patches or faded colors, and the loss can be permanent. Risk factors include smoking, diabetes, high blood pressure, sleep apnea, anemia and kidney disease, and someone who has had it in one eye faces a higher risk in the other.

What patients are told to do: The FDA says anyone on these drugs who notices those symptoms should contact a health care professional right away, and doctors should refer suspected cases promptly to an ophthalmologist. Patients who have had NAION should talk with their doctor about whether to keep taking the drug; the agency tells doctors to consider stopping it unless the benefits clearly outweigh the risk. The FDA did not tell other patients to stop.

What the numbers mean: In the FDA's pooled analysis of 126 clinical trials with 134,253 patients, there were 10 probable NAION cases among GLP-1 users and 5 among comparison patients, or 6.4 versus 3.8 cases per 100,000 patient-years. That works out to about 2.6 extra cases per 100,000 patient-years, roughly 1.7 times the comparison rate, from a small number of total cases. In a separate FDA real-world study of adults with type 2 diabetes, GLP-1 users had a higher NAION rate than people starting DPP-4 inhibitors such as Januvia, but no statistically significant difference from people starting SGLT-2 inhibitors such as Jardiance.

How the companies responded: Lilly spokesperson Misty Fuller said the company will "remain in close contact with the agency and continue to review all available data, including any data regarding ophthalmic events," Bloomberg reported. Novo Nordisk said it will keep reviewing new research and monitoring safety and is confident in the benefit-risk profile of its drugs, according to Bloomberg.

How we got here: The review began after a July 2024 study in JAMA Ophthalmology from a single Boston health system linked semaglutide, the ingredient in Ozempic and Wegovy, to a higher NAION risk. The FDA said that study had several limitations but warranted a full look at trial, animal and real-world data. Bloomberg reported that four patients who developed the condition won compensation in Denmark last year.

What's still unknown: The FDA calls the risk "potential" and said its review of animal data found no mechanism for how the drugs could cause NAION. Adverse-event reports are hard to read because diabetes and other conditions common among GLP-1 users are themselves risk factors, the agency said, and it did not say when the new label language must appear.

Figures are from the FDA's Nov. 9, 2026 Drug Safety Communication. The 6.4 and 3.8 rates come from 10 and 5 probable NAION cases in 156,947 and 131,932 patient-years of exposure; the 2.6-case difference and the roughly 1.7-times ratio are US Brief's arithmetic from those numbers. The FDA calls the risk "potential" and said its animal data review found no mechanism. Company statements were reported by Bloomberg. The Denmark compensation detail is Bloomberg's reporting.