Most people with open-angle glaucoma don’t have symptoms. If symptoms do show up, they’re usually late in the disease. That’s why glaucoma is often called the “sneak thief of vision.” The main sign is usually loss of side, or peripheral, vision.

With any type of glaucoma, you may experience:

• Eye pain or pressure.
• Headaches.
• Rainbow-colored halos around lights.
• Low vision, blurred vision, narrowed vision (tunnel vision) or blind spots.
• Nausea and vomiting.
• Red eyes.

Glaucoma damage is irreversible, so you need early detection and treatment to prevent blindness.