Glaucoma: Types, Symptoms, and Treatment

Article | October 2019

Glaucoma: Types, Symptoms, and Treatment

Learn about this eye disease and who is most at risk.

Glaucoma is an eye disease that damages the optic nerve, and it can gradually lead to blindness. The optic nerve is like an electric cable that carries information from the eye to the brain. If the nerve becomes damaged, you can lose your vision. Glaucoma is one of the most common causes of blindness in the world.

Glaucoma can occur at any age, but it most often affects the middle-aged and elderly.

What are the main types of glaucoma?

There are 2 main types of glaucoma:

  • Open-angle glaucoma (OAG) is the most common form in the U.S. and Canada. It usually affects both eyes at the same time. Although it gradually causes vision to get worse, it happens so slowly that you might not notice it in the early stages.
  • Closed-angle glaucoma (CAG) can occur suddenly and be a medical emergency. It usually affects 1 eye at a time.

What causes glaucoma?

The exact cause of glaucoma is unknown. In some cases, increased pressure in the eye (intraocular pressure) causes nerve damage, but some people with glaucoma have normal eye pressure.

Your risk for glaucoma increases if you:

  • Are over 40, as the chance of developing glaucoma gets higher as you age
  • Have a family history of glaucoma
  • Have high eye pressure
  • Are African American, East Asian, or Hispanic
  • Are farsighted
  • Have had an eye injury or eye surgery
  • Have diabetes
  • Have high blood pressure (hypertension)
  • Long term use of corticosteroids

What are the symptoms of glaucoma?

At first, people with glaucoma lose their side (peripheral) vision. But if the disease isn’t treated, vision loss may worsen. This can lead to total blindness.

If you have Open-Angle Glaucoma (OAG), the only symptom you might notice is loss of vision. And you may not notice this until it is serious.

Closed-angle Glaucoma (CAG) symptoms can be mild, such as temporary blurred vision. Severe signs of CAG include longer episodes of blurred vision or pain in or around the eye. You may see colored halos around lights, have red eyes, or feel sick to your stomach.

How is glaucoma diagnosed?

Glaucoma can be diagnosed during comprehensive eye exams with your eye doctor. Your primary care provider may recommend you see an eye doctor to screen for glaucoma. 

What is the treatment for glaucoma?

Glaucoma treatment can include eye drops, medication, surgery, or a combination of these approaches. Although there is no cure for glaucoma, the good news is that it can be managed if detected early, and with treatment most people with glaucoma do not lose their sight.

More Information

Learn more about glaucoma by visiting the Glaucoma Foundation website. 

Man at the eye doctor getting eyes checked