Can weight-loss drugs like Ozempic and Mounjaro cause vision loss? Here’s what we know so far
NAION is a condition in which sudden loss of vision occurs because of a painless reduction in blood flow to the optic nerve. It is often referred to as an “eye stroke”.
- Sep 24, 2026,
- Updated Sep 24, 2026 12:00 PM IST
Several people in the US have sued the companies behind popular GLP-1 drugs such as Ozempic and Mounjaro, alleging that the medicines caused a rare eye condition that can lead to permanent vision loss, Aljazeera reported on Tuesday.
The lawsuits centre on nonarteritic anterior ischemic optic neuropathy (NAION), an eye condition that occurs when there is inadequate blood flow to the optic nerve, potentially causing permanent vision loss.
The legal cases could pose a challenge to the rapidly growing GLP-1 industry, which analysts have expected to generate about $100 billion in annual sales over the next 10 years.
The drugs have been taken by millions of people in the US and have become a major tool in tackling widespread obesity in the country.
What is NAION?
NAION is a condition in which sudden loss of vision occurs because of a painless reduction in blood flow to the optic nerve. It is often referred to as an “eye stroke”.
The damage is usually irreversible, although the condition itself is rare.
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Scientific research has pointed to possible cases in which patients taking GLP-1 drugs were more likely to develop NAION. However, researchers have not established whether the medicines cause the condition.
Researchers have said that among people who develop NAION while taking GLP-1 medication, it occurs within the first six to 18 months of starting treatment.
What do the lawsuits allege?
A personal-injury firm in the US called Weitz & Luxembourg has filed more than 90 lawsuits against Novo Nordisk in a New Jersey state court since 2025 on behalf of patients who developed NAION while taking its products.
Separate lawsuits have also been filed in the US District Court for the Eastern District of Pennsylvania.
A woman in Pennsylvania told The Washington Post that after taking medication for her diabetes, her vision was like looking through a “fishbowl”. Two weeks later, she was diagnosed with NAION.
Novo Nordisk, which makes Wegovy and Ozempic, has rejected the allegations.
A spokesperson for the pharmaceutical giant said the lawsuits lacked merit and that the company was vigorously contesting them, according to The Wall Street Journal.
Eli Lilly, which produces Zepbound, did not comment on the litigation but said it was reviewing the data on potential health risks.
What does the research say?
Scientists have been studying a possible connection between NAION and GLP-1 drugs for years, but research findings have remained mixed.
A Novo Nordisk company-funded study involving randomised trials of GLP-1 patients found that the drugs do not cause any increase in the risk of NAION.
Dr Tina Vilsboll, a senior medical officer at Novo Nordisk and the lead author of the study, said she sees “no causality” and there are no “indications that we should really be worried about NAION”.
The European Medicines Agency said NAION could affect one of every 10,000 GLP-1 users who have diabetes.
The North American Neuro-Ophthalmology Society and the American Academy of Ophthalmology said that despite reports of a small possible increase in risk, some studies have found no correlation. They said “the overall magnitude of the risk of NAION remains low.”
FDA investigating possible link
Despite the lawsuits, the US has not added any warnings about NAION to GLP-1 medications.
The US Food and Drug Administration has been investigating the possible link between the drugs and the eye condition after early reports of a connection emerged in 2024.
Several people in the US have sued the companies behind popular GLP-1 drugs such as Ozempic and Mounjaro, alleging that the medicines caused a rare eye condition that can lead to permanent vision loss, Aljazeera reported on Tuesday.
The lawsuits centre on nonarteritic anterior ischemic optic neuropathy (NAION), an eye condition that occurs when there is inadequate blood flow to the optic nerve, potentially causing permanent vision loss.
The legal cases could pose a challenge to the rapidly growing GLP-1 industry, which analysts have expected to generate about $100 billion in annual sales over the next 10 years.
The drugs have been taken by millions of people in the US and have become a major tool in tackling widespread obesity in the country.
What is NAION?
NAION is a condition in which sudden loss of vision occurs because of a painless reduction in blood flow to the optic nerve. It is often referred to as an “eye stroke”.
The damage is usually irreversible, although the condition itself is rare.
Don't Miss: Hurun India Rich List 2026: Adani reclaims top spot with ₹9.23 lakh cr valuation. Check where others stand
Scientific research has pointed to possible cases in which patients taking GLP-1 drugs were more likely to develop NAION. However, researchers have not established whether the medicines cause the condition.
Researchers have said that among people who develop NAION while taking GLP-1 medication, it occurs within the first six to 18 months of starting treatment.
What do the lawsuits allege?
A personal-injury firm in the US called Weitz & Luxembourg has filed more than 90 lawsuits against Novo Nordisk in a New Jersey state court since 2025 on behalf of patients who developed NAION while taking its products.
Separate lawsuits have also been filed in the US District Court for the Eastern District of Pennsylvania.
A woman in Pennsylvania told The Washington Post that after taking medication for her diabetes, her vision was like looking through a “fishbowl”. Two weeks later, she was diagnosed with NAION.
Novo Nordisk, which makes Wegovy and Ozempic, has rejected the allegations.
A spokesperson for the pharmaceutical giant said the lawsuits lacked merit and that the company was vigorously contesting them, according to The Wall Street Journal.
Eli Lilly, which produces Zepbound, did not comment on the litigation but said it was reviewing the data on potential health risks.
What does the research say?
Scientists have been studying a possible connection between NAION and GLP-1 drugs for years, but research findings have remained mixed.
A Novo Nordisk company-funded study involving randomised trials of GLP-1 patients found that the drugs do not cause any increase in the risk of NAION.
Dr Tina Vilsboll, a senior medical officer at Novo Nordisk and the lead author of the study, said she sees “no causality” and there are no “indications that we should really be worried about NAION”.
The European Medicines Agency said NAION could affect one of every 10,000 GLP-1 users who have diabetes.
The North American Neuro-Ophthalmology Society and the American Academy of Ophthalmology said that despite reports of a small possible increase in risk, some studies have found no correlation. They said “the overall magnitude of the risk of NAION remains low.”
FDA investigating possible link
Despite the lawsuits, the US has not added any warnings about NAION to GLP-1 medications.
The US Food and Drug Administration has been investigating the possible link between the drugs and the eye condition after early reports of a connection emerged in 2024.