What is glaucoma?

Glaucoma is caused when pressure builds up inside the eye, damaging the optic nerve that connects the eye to the brain. If it’s not treated in time, it can cause irreversible blindness.

An eye health worker shines a torch into a woman's eyes to check for eye issues. She's wearing a colourful pink headscarf.

It’s thought that 4.5 million people across the globe are blind because of glaucoma, making it the third highest cause of blindness worldwide.

The condition can be difficult to diagnose because symptoms don’t appear straight away – instead, they develop slowly over many years. This means many patients only seek treatment when they notice they’re losing their sight, when significant damage has already occurred.

Glaucoma is a group of conditions caused by normal fluid in the eye that hasn’t drained properly. This creates pressure that damages the optic nerve connecting the eye to the brain, resulting in sight loss. Although it’s not clear exactly why this happens, factors such as age, family history, racial background and other medical conditions such as diabetes and short-sightedness can increase the risk. It can affect people of all ages, but it’s most common in adults.

There are different types of glaucoma, and treatment will depend on the type a patient has. Glaucoma can’t be cured, and vision that has already been lost cannot be restored. But further sight loss can be prevented via medication or surgery. Each glaucoma patient requires lifelong management for best results.

Optometrist Mohammed checks a patient's eyes.

The Keep Sight initiative

To tackle glaucoma in India and Nigeria, Sightsavers is working with pharmaceutical company Allergan and the International Agency for the Prevention of Blindness (IAPB).

About the project
76 million
people worldwide are affected by glaucoma
95.4 million
people are likely to be affected by 2030
of glaucoma vision loss occurs without any symptoms

How is glaucoma treated?

Eye drops

The most common type of glaucoma is usually treated with eye drops that reduce the pressure in the eye. This treatment will need to be continued throughout the person’s life.

Surgical staff perform a cataract operation.


Laser treatment or surgery can correct the problem that initially caused the fluid build-up. Laser treatment is fairly straightforward and usually takes about 15 minutes.

What we’re doing

Sightsavers treats and prevents eye conditions including glaucoma in the countries where we work.

Yet the challenge is that patients often don’t seek treatment for glaucoma until it is too late to save their sight. This is why we are working with partners in Africa to introduce pilot programmes to prevent and treat glaucoma.

Our aim is to make sure glaucoma is diagnosed and treated as part of local eye health services, to ensure patients’ sight can be saved.

Learn more about what we do


Fighting “the silent thief of sight”

As part of a Sightsavers-supported project in Nigeria, eye surgeons are learning new ways to treat patients with glaucoma.

About the project

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