A new study from researchers in Canada has raised a warning: a popular drug used for diabetes and weight loss may more than double the risk of developing a dangerous eye disease called neovascular age‑related macular degeneration (nAMD), especially in older adults with diabetes.
The drug in question is semaglutide, sold under brand names like Ozempic and Wegovy. It belongs to a class called GLP‑1 receptor agonists. These medications have become very popular because they help control blood sugar and also help many people lose weight.
Their benefits for heart health have also been an important selling point. However, this new research suggests that there may be a hidden risk for eye health, especially over long periods of use.
Age‑related macular degeneration (AMD) is a leading cause of vision loss in older adults in Western countries. Normally, AMD has two types: “dry” and “neovascular” (the wet form). The wet or neovascular form is the more serious one—it involves abnormal blood vessels growing under the retina (the layer of cells in the back of the eye that senses light).
These vessels can leak fluid or blood and damage the macula, the central part of the retina that gives us sharp, central vision. When that area is damaged, people can lose their ability to see faces, read, or do detailed work.
In this new study, published in JAMA Ophthalmology, researchers in Ontario looked at the medical records of 139,002 people aged 66 and older who had diabetes between 2020 and 2023. Of those, 46,334 people had taken semaglutide or another GLP‑1 drug for at least six months, while the remaining 92,668 had never used these drugs.
The researchers compared the two groups, using statistical methods to try to account for differences in health conditions, age, and other factors. They found that people who used GLP‑1 drugs had a significantly higher risk of being diagnosed with neovascular AMD.
The adjusted hazard ratio was 2.21, meaning more than double the risk compared to those who didn’t use these drugs. The risk went up even higher for people who had used the drug for more than 30 months—the hazard ratio jumped to 3.62, or more than three times the risk.
They also found that older age and having had a stroke or other blood vessel problems in the brain further increased the risk of developing nAMD among those using the drugs. That means some people are especially vulnerable.
This is not the first time the possible eye risks of semaglutide have been noticed. In earlier clinical trials—specifically SUSTAIN 6 and PIONEER 6—some participants taking semaglutide showed more diabetic eye problems. There have also been rare reports of damage to the optic nerve.
Yet, until now, evidence has been mixed. Some laboratory studies even hinted semaglutide might be protective for the eye. Because of that conflicting evidence, many experts remained cautious about drawing strong conclusions.
What makes this new study stand out is its large size and real-world data over multiple years in older adults. That gives it weight in the medical community.
Still, the study does not prove that semaglutide causes nAMD. It shows a strong link—but there could be other reasons involved. For example, people who take semaglutide might have more severe diabetes, more risk factors, or other health conditions that also affect eye health.
The researchers acknowledge these limitations and call for further investigation to understand whether the drug itself or other underlying factors are driving the increased risk.
In the meantime, their recommendation is cautious but clear: doctors should monitor the eye health of patients who use semaglutide or other GLP‑1 drugs, especially if they use them long-term.
Regular eye exams might help catch early signs of damage before vision is lost. As the use of semaglutide continues to rise—both for diabetes and weight loss—these findings highlight the importance of watching for side effects that may take years to become obvious.
For patients, this research doesn’t necessarily mean stopping semaglutide suddenly. Stopping a diabetes drug can have serious health consequences.
Instead, if you are using one of these medications, especially for a long time, it’s reasonable to talk with your doctor or eye specialist about regular retinal screening and keeping an eye (pun intended) on any visual changes.
This study is a reminder that even drugs that bring strong benefits—like controlling blood sugar or helping with weight—can carry risks that emerge over time. As more people use these therapies, ongoing research and vigilance are essential.
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