Blindness Concerns Over Ozempic, Doctors Explain the Risks.
Concerns are rising over whether Ozempic, the popular diabetes and weight-loss drug, could be linked to blindness. Lawsuits are mounting against its manufacturer, Novo Nordisk, citing cases of non-arteritic anterior ischemic optic neuropathy (NAION) — a rare form of vision loss. But medical experts warn the picture is more complex than it appears.
A Rare Eye Condition at the Centre
NAION is the second leading cause of optic nerve blindness and can cause permanent vision loss. The condition occurs when blood flow to the optic nerve is reduced. It often affects people with diabetes, high blood pressure, or sleep apnea, according to Brigham and Women’s Hospital.
The sudden onset of NAION makes it frightening. “It can develop over days,” explains Dr. Joseph Rizzo, director of neuro-ophthalmology at Mass Eye and Ear.
What the Research Reveals
Recent studies have attempted to understand if semaglutide — the active ingredient in Ozempic and Wegovy — is tied to NAION.
A 2024 study by JAMA Ophthalmology reviewed records from more than 17,000 patients treated at Mass Eye and Ear between 2017 and 2023. Researchers found that 11 percent of patients with diabetes who took semaglutide developed NAION, compared with 3 percent who used other medications.
A broader 2025 study analyzing data from 37.1 million adults with type 2 diabetes found a smaller link. Researchers concluded the risk was present, but less significant than earlier findings suggested.
Another study in August 2025, published in JAMA Network Open, followed 159,000 people using semaglutide or tirzepatide. Only 0.04 percent developed NAION, compared with 0.02 percent in the comparison group. Researchers described the increase as slight but statistically noticeable.
Are the Numbers Truly Concerning?
The results may sound alarming, but experts urge caution.
Dr. Howard Krauss, a surgical neuro-ophthalmologist at Pacific Neuroscience Institute, says context is key. He points out that Mass Eye and Ear is a specialty center that sees more severe cases, which could skew the data.
He also raises another possibility: patients prescribed semaglutide may already be sicker and at higher risk. “Is there a compounding factor that those with more severe diabetes or obesity were more likely prescribed semaglutide?” he asks.
Since diabetes itself raises the likelihood of NAION, as do common complications like high blood pressure, the connection may not be about the drug alone.
A Rare and Unusual Side Effect
Doctors emphasize that NAION is extremely rare in patients taking semaglutide.
“This is a rare and unusual side effect,” says Dr. Mir Ali, medical director at MemorialCare Surgical Weight Loss Center in California. “The vast majority of people using these drugs will not experience it.”
Dr. Rizzo adds that the research does not prove causation. “The study does not prove cause and effect,” he stresses. “It only shows an association.”
Does the Risk Extend Beyond Diabetes Patients?
So far, research has primarily focused on patients with type 2 diabetes and those with obesity. Whether the same risks apply to individuals taking the drug solely for weight loss remains unclear.
Dr. Krauss notes that because the data doesn’t prove semaglutide directly raises NAION risk, it’s impossible to draw sweeping conclusions.
What Patients Should Know
Experts agree on one thing: more research is needed.
“The data don’t allow us to conclude semaglutide increases NAION risk,” says Dr. Krauss. “But they do suggest a hypothesis worth testing.”
Until then, doctors advise caution but not panic. Regular eye exams remain essential, especially for those with diabetes or related conditions.
Dr. Rizzo urges patients not to overreact. “People should not be alarmed,” he says. “But they should take their eye health seriously and maintain routine checkups.”
For now, the link between Ozempic and vision loss remains under investigation. While the lawsuits grow, experts remind patients that the science is still evolving — and the true risk may be smaller than headlines suggest.
