Legal Challenges Arise Over GLP-1 Receptor Agonists and Vision Loss Risks

Consumers have initiated legal action against the makers of GLP-1 receptor agonists, raising concerns about the potential connection between these drugs and a rare form of vision loss. According to The Wall Street Journal, the lawsuits assert that these medications have led to nonarteritic anterior ischemic optic neuropathy (NAION), a condition where blood flow to the optic nerve is drastically reduced, resulting in sudden vision impairment.

NAION, described by both the American Academy of Ophthalmology and the National Eye Institute as an ‘eye stroke,’ is the most prevalent cause of acute optic nerve injury in adults over 50 years old. Dr. Douglas Lazzaro from NYU Langone Health stated that no treatment is currently available for this condition, which could lead to significant vision loss.

“The problem with NAION is there’s no treatment,” Dr. Lazzaro told Fox News Digital. “So it can cause some very profound vision loss.”

Novo Nordisk and Eli Lilly, manufacturers of key GLP-1 drugs such as Ozempic, Wegovy, Mounjaro, and Zepbound, contest the claims, asserting no increased risk in causing NAION.

Research Insights

Most studies focus on semaglutide rather than tirzepatide. A 2025 study published in JAMA Ophthalmology analyzed data from 37 million adults. It found that semaglutide users showed a slight increase in NAION risk compared to users of SGLT2 inhibitors, another diabetes medication. A 2024 Harvard study reflected similar findings with higher relative risk yet noted the absolute risk remained low.

Despite observational research indicating a potential link, more data is needed to establish the drugs as a cause for NAION. The FDA continues to review evidence but has yet to issue warnings for semaglutide drugs. Meanwhile, Europe’s agency suggests labeling NAION as a rare adverse reaction.

Understanding NAION

NAION typically presents with sudden, painless vision loss in one eye. Other symptoms like blurred vision or loss of color vision may occur. Factors such as diabetes, high blood pressure, cholesterol, and smoking are major risk contributors.

“So if I had a patient who had what I would see on exam is a disk at risk, a very compact optic nerve where everything’s crowded, I would tell that patient probably to not go on a semaglutide,” Lazzaro advised.

For individuals taking GLP-1 medications, underlying conditions like diabetes can complicate the determination of drug effects versus disease impacts on NAION risk.

Vision loss from NAION often remains permanent, although partial vision might be regained over time. Within studied populations, NAION occurs in about two to ten cases per 100,000 people yearly.

Nonetheless, patients are advised not to discontinue GLP-1 medications without consulting healthcare providers, as the benefits may surpass potential vision risks.

Actions and Considerations

Dr. Lazzaro highlights the importance of assessing risks versus benefits.

“My overall take on the matter is there’s probably a slightly increased risk of NAION when using the semaglutides, but I think the health benefits outweigh the risks,” he explained. “And unless I have a patient with a disk at risk, I would probably tell them to go on them if they’re going to be a lot healthier from an overall standpoint.”