FDA orders GLP-1 weight-loss drug makers to add warning about rare vision loss risk

The Food and Drug Administration said GLP-1 drugs, including Ozempic, Wegovy, Zepbound and Mounjaro, may carry a potential increased risk of a rare eye condition that can cause permanent vision loss. In a drug safety communication, the agency said makers of these drugs must add a warning about the risk to their labels. The warning applies to a dozen pill and injectable drugs. The condition is non-arteritic anterior ischemic optic neuropathy, or NAION, which occurs when blood flow to the optic nerve is reduced. The FDA said its underlying cause remains unclear. An FDA review of 126 clinical trials involving 134,253 patients found about six cases per 100,000 patients over a year on GLP-1 drugs, compared with fewer than four among those on placebo or other glucose-lowering medicines. Patients on GLP-1 drugs had a roughly 68% higher rate, but the agency said the findings do not establish a causal link. The FDA began investigating in 2024 after a study found some patients taking semaglutide experienced this type of vision loss. That study had limitations, including that patients came from a single referral center. Risk factors for NAION, such as diabetes and high blood pressure, are also common among people taking these drugs.

NAION is most common in adults over 50 and often causes sudden, painless vision loss in one eye. There is no proven treatment to reverse the damage, though about 43% of patients with significant vision impairment see some spontaneous improvement, according to research cited by the FDA.