Hesperian Health Guides

Common Eye Problems

In this chapter:


 eye with pupil covered with white

The lens is a clear part inside the eye that focuses the light from outside so the eye can see. As people get older, the lens can become cloudy, blocking light from shining through it, and leading to a gradual loss of vision and eventual blindness. This cloudiness can sometimes be seen as a gray spot on the eye, called a cataract. Cataracts are most common in older people, but may occur in babies and children.

To delay the development of cataracts:

  • Don’t smoke.
  • Wear hats to protect the eyes from strong sunlight.
 health worker speaking
We say: “If there is gray hair, check for gray eyes.” We encourage older people with cataracts to get the operation to bring back their vision.

Health workers can identify people with cataracts and recommend programs and hospitals that offer operations to restore sight. Women are less likely than men to get treatment for cataracts. Visit older women in their homes and ask about their eyesight. Checking older people can help them get treated before cataracts block their vision. But even if they can barely see, it is never too late to get them help.


Medicines do not help a cataract go away. An operation removes the cataract (the cloudy lens) and puts in a clear lens so the person can see again.

After the operation, the person will need antibiotic and antiinflammatory eye drops to help the eye heal, usually for about 4 weeks. The eye may be slightly uncomfortable and seeing can be blurred at first, but this should improve a little each day. If pain in the eye develops in the first two weeks, this is a danger sign. Get help from an eye doctor within 24 hours. Reading glasses may be needed after the operation in order to see close up.


Sometimes pressure increases inside the eye and damages nerves inside the eye, causing a serious disease called glaucoma. A person with glaucoma loses side vision and gradually can become blind. The eye may hurt and get hard like a marble. Glaucoma may be caused by an injury, but most often the cause is unknown.

A person with glaucoma needs treatment to lower the pressure. This may be eye drops daily for the rest of their life, or sometimes laser treatment or an operation is used to lower the eye pressure.

Glaucoma mostly affects people who are older than 40, especially those who have had a family member with glaucoma. Help people over 40 get their eyes checked for glaucoma every few years.

There are different forms of glaucoma. Most common are acute glaucoma and chronic glaucoma.

Acute glaucoma (angle-closure glaucoma)

This worsens very quickly. It causes a red and very painful eye with loss of vision. The person may feel nausea, have a headache, and their eye hurts more in bright light. The eye may feel hard compared to the other, normal eye. If not treated, acute glaucoma will cause blindness within a few days. Send the person for medical help immediately. They will first need eye drops that lower the pressure in the eye. Then they will likely need laser treatment or an operation.

Chronic glaucoma (open-angle glaucoma)

In chronic glaucoma, the pressure in both eyes increases slowly over months and years. There is no pain. Side (peripheral) vision is lost first. As the glaucoma gets worse, it is like looking through a tunnel. The person often does not notice until vision loss is severe. Eye doctors can test side vision and look inside the eye to check for this kind of glaucoma. The earlier it is treated, the better. Treatment with eye drops, laser, or surgery can stop vision from getting worse.

Fleshy growth across eye (pterygium)

 eye with strip of flesh coming out of inner eye, covering part of white of eye and iris

A fleshy thickening on the eye surface that slowly grows out from the white part of the eye near the nose and toward the middle is called a pterygium. It is common and usually not serious. People who spend many years working outside in strong sunlight or where there is wind or dust are more likely to have them.

Wearing dark glasses and hats helps keep sunlight, wind, and dust away from the eyes, which prevents or slows the growth.

Often these need no treatment. If it is too close to the colored part of the eye or causes too much discomfort, the growth can be removed by an eye surgeon before it begins to affect the person’s vision.

Blood in the white of the eye

 eye with blood covering bottom area
A patch of blood in the white part is usually harmless.

Blood in the white of the eye occasionally appears after lifting something heavy, coughing hard, or a minor injury to the eye. It results from the bursting of a tiny blood vessel. It is harmless, like a bruise, and it will slowly disappear on its own within 2 weeks. No treatment is needed.

However, if blood is in the colored part of the eye (the iris), this is serious.

Dry eyes and crusty eyelids

Dry eyes are caused by dry climates, getting older, smoke in the air, and some medications.

Crusty eyelids can happen when dirt or discharge blocks moisture and tears, making eyes dry and itchy. The person may get eyelid infections (see below) or crust or dandruff-like flakes along the eyelid. When the eyelids and face around the eyes are clean, the tears and natural moisture of the eyes can keep them healthy.


For dry eyes, rest your eyes by closing them now and then. If your eyes stay dry, you can try warm compresses 1 to 2 times a day for 5 to 10 minutes to increase the natural moisture in the eyes. Lubricating eye drops can also help.

For crust on the eyelids, use warm compresses 2 to 4 times a day, followed by a gentle washing of the eyelids. If it does not improve, there may be a bacterial infection and you can try erythromycin antibiotic eye ointment 2 times a day for 7 days.

Lumps and swelling on the eyelids

A red swollen lump on the eyelid usually is either:

  • a stye, a painful lump caused by an infection around an eyelash; or
  • a chalazion, a lump that may not hurt, caused by blockage inside the eyelid.

Sometimes an infection that starts around an eyelash can spread to inside the eyelid.

Both can be treated with warm compresses 4 times a day for 15 or 20 minutes each time. Re-heat the cloth several times while using to keep it as warm as possible without burning. Do not squeeze or puncture the lump as this makes the problem worse.

If swelling does not lessen in a few days, get medical help.

 eye with bump in middle of lower eyelid
 eye with bump under upper eyelid
A stye is a painful infection around the eyelash. A lump under the eyelid that does not hurt may be a chalazion.

Floaters (seeing small spots)

Floaters or small moving spots are sometimes seen when looking at a bright surface (like a wall or the sky). The spots move when the eyes move and look like tiny flies. These spots are common and usually harmless.

If large numbers of floating spots appear suddenly and vision begins to fail in one eye, or you also continue to see flashes of light, this could be a sign of a condition called a detached retina. A surgery at an eye hospital is needed as soon as possible to reattach the retina.

Vitamin A deficiency (night blindness, xerophthalmia)

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Lack of vitamin A is a type of malnutrition that can damage the eyes of children, causing blindness. This is preventable.

Protect the eyes of small children by making sure they eat foods rich with vitamin A, including orange foods such as carrots, mango, and papaya, and green leafy vegetables, fish, and eggs. Breastfeeding helps protect a baby’s eyes from lack of vitamin A along with providing many other benefits for the baby’s health.

Where this type of malnutrition is common, sometimes all children are given a vitamin A supplement every 6 months.


First, the eyes become dry and produce less tears. Then there is more difficulty seeing in dim light. The white part of the eye loses its shine and starts to wrinkle. Eventually the eyes become more damaged and the child may become blind.


If a child cannot see well in the evening or if the child has measles, then treat the child with vitamin A.

Crossed eyes, wandering eye, squint (strabismus)

If one or both eyes of a baby or a child do not look straight, this condition can lead to a loss of vision in the wandering eye. Get the child to an eye specialist. It is not an emergency, but the child should go as young as possible to have the best chance of correcting his vision.


The eye doctor may patch the good eye to make the wandering eye work better or prescribe special glasses to help. An operation can usually straighten the eye but is often not necessary.

NWTND eye Page 24-1.png
Sometimes patching the good eye will help the wandering eye become straight and better at seeing. Some children need the patch a few hours a day and some will need to wear it all day.

Pregnancy and vision

Changes in hormones can cause a woman’s vision to change during pregnancy, but usually after the baby is born her vision goes back to the way it was.

Pregnant women who suddenly have blurred vision, see spots, lose vision in one eye, or have double vision could be having danger signs of a serious condition called pre-eclampsia. Pre-eclampsia also brings headaches and high blood pressure (140/90 or higher). Get help right away.

Help pregnant women get tested for gonorrhea and chlamydia and to receive treatment if they need it. Women can have either of these illnesses that are passed during sex and not know it. If these germs spread to the baby’s eyes during birth, the baby can lose her sight.

Protect pregnant women from rubella and Zika, illnesses that can cause serious eye problems in babies. Rubella (German measles) is prevented by a vaccine. For more information on Zika and how to prevent it, see Malaria, Dengue, and Other Illnesses from Mosquitoes.

This page was updated:05 Jan 2024