metformin serves as a protective agent against glaucoma

What is Glaucoma?

Glaucoma is a group of eye diseases that damage the optic nerve—the nerve that connects your eye to your brain. This damage can lead to permanent vision loss if not treated. Glaucoma is the leading cause of irreversible blindness worldwide.

Important to know: Many people with glaucoma have no symptoms in the early stages. About half of people with glaucoma don't even know they have it. This is why regular eye exams are so important.

Common symptoms of glaucoma include:

• Difficulty seeing in your peripheral (side) vision

• Trouble with driving and mobility

• In advanced stages, difficulty with reading and central vision

How Does Diabetes Affect Your Risk of Glaucoma?

If you have diabetes, you have a higher risk of developing glaucoma. Research shows that people with diabetes are about 40-50% more likely to develop glaucoma compared to people without diabetes.

The longer you've had diabetes, the higher your risk:

• Your risk of glaucoma increases by about 5% for each year you've had diabetes

• People who have had diabetes for 5 or more years have nearly 4 times the risk compared to those with diabetes for less than 5 years

Why does diabetes increase glaucoma risk?

Diabetes can cause changes in the small blood vessels that supply your optic nerve, making it more vulnerable to damage.

New Research: Metformin May Help Protect Your Eyes

Recent research has found some encouraging news: metformin, a common diabetes medication, may help reduce your risk of developing glaucoma by about 19%.

What is metformin?

Metformin is the most commonly prescribed medication for type 2 diabetes. It helps lower blood sugar by:

• Reducing the amount of sugar your liver makes

• Helping your muscles use sugar more effectively

• Improving how your body responds to insulin

How might metformin protect your eyes?

Scientists believe metformin may protect against glaucoma through several mechanisms:

• Reducing inflammation in the eye

• Protecting the nerve cells in your retina and optic nerve

• Acting as an antioxidant to reduce cell damage

Important: The protective effect appears to be independent of metformin's blood sugar-lowering effects. This means metformin may help protect your eyes through different pathways than just controlling your diabetes.

The Bottom Line

If you have diabetes, you're at higher risk for glaucoma. The good news is that metformin—a medication many people with diabetes already take—may help reduce this risk by about 19%. However, metformin is not a substitute for regular eye exams or proper glaucoma treatment if you develop the disease.

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