FDA Adds Rare Vision-Loss Warning To All GLP-1 Diabetes And Weight Drugs

The Food and Drug Administration said Monday it is adding a warning about a rare form of serious vision loss, known as non-arteritic anterior ischemic optic neuropathy, to the labels of all GLP-1 diabetes and weight-loss drugs sold in the United States, including blockbuster brands Ozempic, Wegovy, Zepbound and Mounjaro.^[1]

In its safety communication, the FDA said a review of more than 125 clinical trials found NAION occurred in about 6 out of every 100,000 patients who used a GLP-1 drug for at least a year, compared with fewer than 4 per 100,000 among people on placebo or other glucose-lowering medicines. The agency stressed the risk remains very low but said NAION can cause significant, often irreversible vision loss, and urged patients taking GLP-1 drugs to seek immediate medical care if they notice new blurred vision, blind spots or changes in color vision.^[1]

The label change applies across an entire class of drugs that has transformed treatment for type 2 diabetes and obesity in recent years, driving record sales and reshaping diet and nutrition culture in the US and abroad. Originally approved to lower blood sugar in people with diabetes, GLP-1 agonists like Ozempic and Mounjaro quickly gained broader use after studies showed they could lead to substantial weight loss, prompting separate approvals for obesity-focused versions such as Wegovy and Zepbound and fueling widespread off-label demand.^[1]

Reports of possible links between GLP-1 drugs and NAION have surfaced in recent observational studies and adverse event databases, but researchers have struggled to determine whether the medicines themselves, underlying conditions such as diabetes and high blood pressure, or chance may explain the cases. The FDA said its review of clinical trial data showed a slight numerical increase in NAION among GLP-1 users compared with control groups, but not a large enough difference to conclusively prove the drugs cause the condition, leading regulators to opt for a classwide warning while calling for continued safety monitoring.^[1]

Novo Nordisk, which makes Ozempic and Wegovy, and Eli Lilly, which makes Mounjaro and Zepbound, said they do not believe current evidence establishes a causal relationship between their drugs and NAION but will work with the FDA on the label updates and continue to track post-market safety reports.^[1] Clinicians quoted in the agency's briefing and in outside coverage have stressed that, for most eligible patients, the proven benefits of GLP-1 drugs in controlling blood sugar, reducing cardiovascular risk and treating obesity are likely to outweigh the small potential increase in NAION risk, but they say the new warnings should prompt frank discussions about eye symptoms and regular vision checks, especially for patients who already have eye disease or vascular problems.^[1]

1. CBS News