A new study links semaglutide, the drug behind Ozempic and Wegovy, to a rare eye condition that can cause sudden blindness!
Ozempic and Wegovy, popular medications prescribed for type 2 diabetes and weight loss, are now being investigated for a surprising potential side effect—a rare eye condition that can cause sudden vision loss. A recent study published in JAMA Ophthalmology found that semaglutide, the active ingredient in both drugs, may be linked to a significantly increased risk of non-arteritic anterior ischemic optic neuropathy (NAION).
What is NAION?
NAION is a medical condition where blood flow to the optic nerve is reduced, damaging the nerve and potentially causing permanent vision loss. The optic nerve acts like a high-speed cable connecting your eyes to your brain. When its blood supply is cut off, which results in — blurry vision or even sudden blindness in one eye. NAION is rare, affecting about 2 to 10 people per 100,000 each year, but it’s the second most common cause of optic nerve-related blindness after glaucoma.
What Did the Study Find?
The study, led by researchers from Mass Eye and Ear at Harvard Medical School, analyzed health records from over 17,000 patients. They discovered that individuals who took semaglutide for diabetes were 4 times more likely to develop NAION than those not on the medication. For patients using the drug for weight loss, the risk increased to over 7 times.
These findings emerged after the team noted an unusual cluster of three NAION cases at their hospital in a single week in 2023 — all involving patients on semaglutide.
Why Is This a Big Deal?
Ozempic and Wegovy have become household names across industrialized countries, thanks to their dramatic results in lowering blood sugar and promoting weight loss. In fact, Wegovy was approved by the FDA in 2021 as a long-term weight management drug for obese or overweight individuals with health risks like high blood pressure or cholesterol.
Given the scale at which these medications are prescribed, even a small increase in the risk of NAION is significant.
Does This Mean You Should Stop Taking Semaglutide?
Not necessarily. Experts, including Dr. Joseph Rizzo, the study’s lead author, stress that the findings are associative, not conclusive. This means the study shows a link, not a proven cause-and-effect relationship.
Further, the research highlights that diabetes and obesity alone did not significantly increase the risk of NAION. However, the combination of semaglutide use and certain conditions — like hyperlipidemia (high cholesterol and fat in the blood) or pre-existing optic nerve problems like glaucoma — could pose additional risks.
Who Might Be at Higher Risk?
- Men with type 2 diabetes
- Overweight or obese individuals with high cholesterol
- People with diabetic retinopathy
- Patients with a history of optic nerve damage
If you or your loved ones fall into any of these categories, it’s crucial to have an open discussion with your healthcare provider about the potential risks and benefits of semaglutide.
Can This Lead to Blindness?
Yes, in severe cases. NAION can cause sudden, painless vision loss, often in one eye. There is currently no cure, and vision rarely improves. That’s why early identification of risk factors — including possibly medications like semaglutide — is essential.
Is There a Safer Alternative?
At present, semaglutide continues to be one of the most effective medications for controlling type 2 diabetes and managing weight. Other GLP-1 receptor agonists, like liraglutide (Saxenda, Victoza), haven’t yet been shown to carry the same risk — but more studies are needed.
What Should You Do If You’re Taking Ozempic or Wegovy?
- Don’t panic — this is preliminary research.
- Talk to your doctor — especially if you notice vision changes or have a history of eye conditions.
- Ask about screening — if you’re at high risk for optic nerve issues.
- Stay informed — research is ongoing, and guidelines may change.
This new research is a powerful reminder of how even beneficial medications can have unexpected risks. Semaglutide has transformed the treatment landscape for diabetes and obesity, but it’s essential to keep a watchful eye — quite literally — on how it affects the body beyond weight and blood sugar. If you or someone you know is using these medications, regular eye checkups and open conversations with healthcare professionals are vital.
Sources:
- Rizzo J. et al. (2024). Association Between Semaglutide Use and NAION. JAMA Ophthalmology.
- Mass Eye and Ear, Popular Prescription Weight Loss Drugs Linked to Uncommon Blinding Condition
- https://pubmed.ncbi.nlm.nih.gov/38958939/
