Man rubs eyes during headache.

Don't Ignore These Early Symptoms of Glaucoma

Glaucoma damages the optic nerve, causing permanent loss of vision. Although vision can't be restored once it's lost, starting treatment when changes in the eye first occur can reduce or prevent vision loss. Recognizing glaucoma risks and early symptoms will help you ensure you receive the treatment you need to preserve your vision.

What Is Glaucoma?

Glaucoma occurs when high pressure inside the eye damages the optic nerve, the pathway between the eyes and the brain. If this nerve is damaged, the brain doesn't receive the information it needs to create a complete image. Optic nerve damage causes full or partial vision loss depending on the extent of the damage.

The most common types of glaucoma are:

  • Open-Angle Glaucoma. This type of glaucoma happens when the aqueous humor, the clear fluid inside the eye, drains too slowly. As the fluid builds up, pressure on the optic nerve increases. Without treatment, damage to the nerve may eventually occur. Despite the higher pressure in the eye, most patients with this type of glaucoma don't notice any changes to their vision at first.
  • Angle-Closure Glaucoma. Angle-closure glaucoma occurs suddenly and happens when the eye's drainage canals become completely blocked. The blockage can happen if the iris, the colored part of the eye, covers the drainage canals. A blockage causes a dangerous increase in pressure inside the eye. Angle-closure glaucoma is a medical emergency and requires immediate treatment to prevent permanent vision loss.

In some cases, glaucoma can happen even if the pressure inside the eye remains normal.

Common Glaucoma Symptoms

Don't wait to see if you feel better if you have severe eye pain accompanied by a headaches and nausea. These symptoms may mean you have angle-closure glaucoma and need emergency treatment. Other symptoms of angle-closure glaucoma include:

  • Blurry Vision
  • Redness
  • Dilated Pupil
  • Hazy Appearance of the Eye
  • Haloes Around Lights
  • Vomiting

Although open-angle glaucoma doesn't cause the same dramatic symptoms as angle-closure glaucoma, you may notice a few of these early symptoms:

  • Peripheral Vision Loss. Open-angle glaucoma may damage your peripheral (side) vision, narrowing your field of vision. Vision loss may first affect side vision closest to your nose, according to the National Eye Institute.
  • Cloudy Vision. Glaucoma could make your vision look a little hazy or blurry at times.
  • Low-Light Issues. Open-angle glaucoma may affect your ability to see well in low or changing light, according to Mass General Brigham.

According to a survey of glaucoma patients, the most common early glaucoma symptoms were blurry vision and needing more light to see. Patients who had higher amounts of vision loss had trouble seeing objects in their side vision and struggled to recognize color differences. These patients also said that they felt as if they were looking at the world through dirty glasses. The research study appeared in the American Journal of the Medical Sciences in 2014.

Glaucoma Risk Factors

Although anyone can develop glaucoma, some people are more likely to get the disease than others.

Risk factors include:

  • Family History of Glaucoma
  • Asian, Hispanic, or African Heritage
  • Eye Injuries
  • High (Strong) Prescription if You Are Nearsightedness or Farsightedness
  • Age (Your risk increases over age 40, according to the American Association of Ophthalmology.)
  • Thin Corneas
  • Steroid Medication Usage, Particularly if Long-Term
  • Thin Optic Nerve

Certain medical conditions may also increase your risk, including high blood pressure, diabetes, migraines, blood circulation issues, and sleep apnea.

Annual visits to the ophthalmologist include a review of your glaucoma risk factors and a test to measure your eye pressure. Your eye doctor will also place special drops in your eyes to dilate (widen) your pupil. Dilation makes it easier for your ophthalmologist to see the optic nerve and spot any changes.

Glaucoma Treatment Options

Ophthalmologists help patients avoid glaucoma-related vision loss with eye drops that reduce pressure or help fluid drain. Laser or traditional surgery improves drainage or creates new drainage paths. Surgery may be needed if eye drops don't lower pressure enough, or if your iris blocks your drainage canals.

Concerned that you may have glaucoma? Contact our office to schedule a visit with the ophthalmologist. If you have any symptoms of angle-closure glaucoma, go to the emergency room immediately.

Sources:

American Academy of Ophthalmology: Understanding Glaucoma: Symptoms, Causes, Diagnosis, Treatment, 3/4/2026

https://www.aao.org/eye-health/diseases/what-is-glaucoma

National Eye Institute: Glaucoma

https://www.nei.nih.gov/eye-health-information/eye-conditions-and-diseases/glaucoma

Mass General Brigham: Early Symptoms of Glaucoma, 1/12/2024

https://www.massgeneralbrigham.org/en/about/newsroom/articles/early-symptoms-of-glaucoma

American Journal of the Medical Sciences: What Do Patients with Glaucoma See? Visual Symptoms Reported by Patients With Glaucoma, 10/27/2014

https://pmc.ncbi.nlm.nih.gov/articles/PMC4206382/

Glaucoma Research Foundation: How Glaucoma Progresses and What You Can Do to Protect Your Vision

https://glaucoma.org/articles/how-glaucoma-progresses-and-what-you-can-do-to-protect-your-vision