Frequently asked questions

Straight answers about glaucoma, tests, treatment and urgent symptoms.

Written by Dr. M. Ali Tawfik Alyouzbaki, MD, OphthalmologistLast updated Sources citedEditorial policy

About glaucoma

Glaucoma is a group of eye diseases that damage the optic nerve, which carries vision from the eye to the brain. Without treatment it slowly narrows side vision and can lead to blindness.

The most common type usually has no symptoms until it's advanced. About half of people with glaucoma don't know they have it. Acute angle-closure glaucoma is the exception: it causes sudden pain, redness, blurred vision and halos.

Family history is a known risk factor. If a parent, brother or sister has glaucoma, tell your eye doctor and ask how often you should be checked.

Yes. Normal-tension glaucoma damages the optic nerve even though pressure is in the normal range. Lowering pressure further still helps many people.

No. Treatment can't restore lost vision, but it can usually stop or slow further loss, especially when started early.

Tests and visits

Someone with one or more signs that could mean glaucoma, such as high pressure or a suspicious optic nerve, but without definite damage. Suspects are monitored, and some are treated if their risk is high.

Field loss is what glaucoma does. Repeated fields show whether your vision is stable or changing, and how fast. Early on, several tests close together help find people who are getting worse quickly.

OCT measures the thickness of the nerve fiber layer around the optic nerve and the ganglion cells near the center of vision. Thinning can appear before field loss.

It depends on the type and stage of glaucoma and how stable it is. Newly diagnosed or changing glaucoma is seen more often; stable glaucoma less often.

Treatment

Not necessarily. SLT laser is an option for many people with open-angle glaucoma or high eye pressure. In a large trial, about three in four people treated first with SLT needed no drops three years later.

Most people feel little more than brief clicks and mild ache. It's done in the office, takes minutes, and most people return to normal activities the same day.

Put it in when you remember, unless it's almost time for the next dose. Don't double up. If you often miss doses, tell your doctor. A simpler plan or laser may suit you better.

Sometimes. In angle closure, removing the lens opens the drainage angle and can lower pressure a lot. In open-angle glaucoma, cataract surgery can be combined with MIGS to help lower pressure.

Many people can. Driving depends on your visual field in both eyes together and on state rules. Ask your doctor to review your fields with driving in mind.

Urgent problems

Sudden eye pain and redness, blurred vision, halos around lights, headache, and often nausea or vomiting. It's an emergency. Go to an emergency department now.

For sudden vision loss, a curtain or shadow moving across your vision, a red painful eye after glaucoma surgery, or any serious eye injury.

Answers draw on the American Academy of Ophthalmology's glaucoma guidelines[1][2][3], the National Eye Institute[4], the CDC[5], the Glaucoma Research Foundation[6], and the LiGHT[7] and EAGLE[8] trials.

Sources and references

  1. Gedde SJ, Bowden EC, Challa P, et al; American Academy of Ophthalmology Preferred Practice Pattern Glaucoma Committee. Primary Open-Angle Glaucoma Preferred Practice Pattern. Ophthalmology. 2026;133(4):P1-P103. doi:10.1016/j.ophtha.2025.12.029 View source
  2. Gedde SJ, Chopra V, Vinod K, et al; American Academy of Ophthalmology Preferred Practice Pattern Glaucoma Committee. Primary Angle-Closure Disease Preferred Practice Pattern. Ophthalmology. 2026;133(4):P153-P201. doi:10.1016/j.ophtha.2025.12.030 View source
  3. Gedde SJ, Lind JT, Wright MM, et al; American Academy of Ophthalmology Preferred Practice Pattern Glaucoma Panel. Primary Open-Angle Glaucoma Suspect Preferred Practice Pattern. Ophthalmology. 2021;128(1):P151-P192. doi:10.1016/j.ophtha.2020.10.023 View source
  4. National Eye Institute. Glaucoma. National Institutes of Health. View source
  5. Centers for Disease Control and Prevention. Announcement: Glaucoma Awareness Month, January 2016. MMWR Morb Mortal Wkly Rep. 2016;65(1):12. View source
  6. Glaucoma Research Foundation. Types of glaucoma. View source
  7. Gazzard G, Konstantakopoulou E, Garway-Heath D, et al; LiGHT Trial Study Group. Selective laser trabeculoplasty versus eye drops for first-line treatment of ocular hypertension and glaucoma (LiGHT): a multicentre randomised controlled trial. Lancet. 2019;393(10180):1505-1516. View source
  8. Azuara-Blanco A, Burr J, Ramsay C, et al. Effectiveness of early lens extraction for the treatment of primary angle-closure glaucoma (EAGLE): a randomised controlled trial. Lancet. 2016;388(10052):1389-1397. View source