The FDA Is Requiring Ozempic, Wegovy and Other GLP-1 Drugs to Warn of a Rare Condition That Can Permanently Damage Vision
by Jerome London · Thought CatalogUpdated 4 minutes ago, November 10, 2026
Sudden vision loss in 1 eye, often without pain, is the risk behind the FDA’s November 9 requirement for new warnings on Ozempic, Wegovy and every other approved GLP-1 drug. The condition, NAION, can leave lasting damage to the optic nerve.
NAION stands for non-arteritic anterior ischemic optic neuropathy. It develops when blood flow to the front of the optic nerve is reduced. People may notice missing areas of vision when they wake up, and there’s no proven treatment that reverses the damage.
The FDA describes a potential increase in risk. Whether these medicines cause NAION remains unproven. Diabetes, high blood pressure, sleep apnea and kidney disease already raise the risk, and many people prescribed GLP-1s have those conditions.
The requirement includes Mounjaro and Zepbound, which contain tirzepatide, as well as semaglutide products such as Ozempic, Wegovy and Rybelsus. Cases have been reported with every marketed GLP-1 product, though most published evidence concerns semaglutide. The evidence doesn’t establish whether some drugs, doses or treatment durations carry greater risk.
The FDA’s review of 126 randomized trials involving 134,253 participants identified 15 probable NAION events: 10 among GLP-1 users and 5 among placebo recipients. Rates were 6.4 cases per 100,000 person-years for GLP-1 users and 3.8 for the comparison groups, a difference of about 2.6 cases per 100,000 people followed for 1 year. Those estimates rest on very few events.
Other findings were mixed. In the FDA’s study of adults with type 2 diabetes, GLP-1 users had a statistically significant increase compared with people starting DPP-4 inhibitors.
The comparison with SGLT2 inhibitors wasn’t statistically significant. Animal studies haven’t identified a mechanism explaining how GLP-1 drugs might cause the injury.
Europe acted on semaglutide in June 2025, classifying NAION as a very rare side effect and recommending updated product information. Its review estimated about 1 additional case per 10,000 person-years in large studies of people with type 2 diabetes. That estimate concerns semaglutide specifically; the U.S. requirement covers the broader drug class.
Novo Nordisk says the evidence doesn’t establish cause and effect. Eli Lilly says it’s evaluating the update and notes that the FDA communication doesn’t cite findings specific to its medicines.
The U.S. warning will go in the prescribing label’s Warnings and Precautions section. Companies can respond before the wording is finalized. The FDA hasn’t ordered a recall or told patients to stop treatment on their own.
The agency advises prompt evaluation by an eye doctor when NAION is suspected. If it develops, prescribers should consider stopping the medicine unless its benefits clearly outweigh the risk, including benefits for diabetes, heart disease or kidney disease. People who’ve already had NAION should discuss their treatment with their clinician because another event, including in the other eye, is more likely.
The FDA says sudden vision loss, new blind spots, washed-out colors or a blurry patch in 1 eye need immediate medical attention. Patients should contact a clinician right away rather than wait for a routine appointment.
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