Glaucoma
Increased eye pressure damages the optic nerve, stealing vision gradually.
A way to think about it
Think of your eye like a plumbing system. Normally, fluid flows in and out smoothly, keeping pressure balanced. In glaucoma, the drain gets blocked or clogged, and pressure builds up inside the eye—like a backed-up sink. This pressure squeezes the optic nerve, which carries sight to the brain.
What's happening in the eye
Your eye produces a clear fluid called aqueous humor that keeps the eye firm and healthy. Normally this fluid drains out through a small channel. In glaucoma, drainage slows or stops, causing pressure to build up. Over months or years, this pressure damages the optic nerve fibers at the back of the eye. You lose peripheral (side) vision first, often without noticing.
Common symptoms
- No symptoms in early stages, sneaky onset
- Blurred or hazy vision in later disease
- Eye pain or redness in acute angle closure
- Halos around lights, especially at night
- Loss of side vision, tunnel vision as it progresses
Risk factors
- Age over 60, especially in African descent
- Family history of glaucoma doubles your risk
- High eye pressure (intraocular pressure)
- Thin cornea or nearsightedness
- Diabetes or high blood pressure
- Prior eye injury or surgery
Treatment options
Warning signs - seek care immediately
- Sudden blurred vision or pain—could be angle closure, get ER care now
- Eye turns red, hurts, and vision blurs suddenly—emergency
- You can't feel your eye drops stinging—may signal nerve damage
- No improvement in vision after starting treatment—discuss with doctor
Questions to ask your doctor
- 1.What is my actual eye pressure number, and what's the target?
- 2.Do I have open-angle or angle-closure glaucoma? How does that change my treatment?
- 3.How often should I get my vision field tested to check for progression?
- 4.Am I a candidate for laser or surgery if drops don't work?
- 5.Should my family members get screened? At what age?
Glaucoma caught early rarely causes blindness if you take drops consistently. The key is catching it before major damage and staying on treatment long-term. Regular eye exams are your best defense.
Sources
Information on this page is based on the following authoritative sources:
- American Academy of Ophthalmology
- National Eye Institute (NIH)
- American Optometric Association
- Mayo Clinic
Last updated: April 2026