People who are abnormally sensitive or intolerant to light are suffering from a medical condition called photophobia, and those who have a blue, gray, or green pigmentation in the iris are more likely to suffer from it than people with dark colored iris. Some underlying health conditions may also lead to light sensitivity.

Symptoms of Light Sensitivity

The most common symptoms of light sensitivity include:

• A feeling of nausea
• Feeling a need to close the eyes frequently
• A burning sensation in the eyes
• Squinting
• Vertigo
• Eye pain
• Watery eyes
• Stiff neck
• Headache

Some people only report the light sensitivity itself, while others claim that the eye becomes sensitive suddenly on one day, and turns to be perfectly normal on the next day. Everyone may experience different symptoms.

Why Are Your Eyes Sensitive to Light?

Although some people with light colored iris are naturally more sensitive to light than others, sensitivity to light could also be the result of some conditions that affect both the eyes and the body.

1. Migraine Headache

Migraine headaches can be triggered by hormones, stress, food and medications. People with migraine headache may have visual problems such as flashes of light at first, followed by a severe pounding headache which is usually on one side of the head. Symptoms of migraine headache may also include:

• Light sensitivity
• Nausea
• Vomiting

2. Meningitis

Meningitis is a viral or bacterial infection which causes inflammation of the membranes surrounding your spinal cord and brain, and it is marked by light sensitivity, intense headache, and muscular rigidity. Symptoms of meningitis may also include:

• A high fever
• A persistent and severe headache
• Stiff neck pain that makes it difficult to touch the chin to the chest
• Nausea with vomiting
• Delirium
• Fatigue or sluggishness
• A loss of appetite
• Seizure and coma in severe cases

3. Corneal Abrasion

The cornea is the clear outer layer covering the eye's iris and pupil, and when it becomes damaged, it’s known medically as a corneal abrasion. The cornea functions by focusing light as it enters the eye, therefore when the cornea is scratched or is scared by an abrasion, your vision can be affected. Symptoms include:

• Eyes sensitive to light
• A feeling that there’s something in your eye
• Pain when opening or closing your eyes
• Watery eyes
• Red eyes
• Blurry vision or loss of vision
• Headache

4. Eye Allergies

Eye allergies or allergic conjunctivitis is an allergic condition that involves inflammation of the thin membrane that covers the inside of the eyelids, and it occurs when the eyes react to an irritant. Common eye allergy symptoms include:

• Eyes sensitive to light
• Itchy, red and swollen eyes
• A burning sensation, with teary eyes

5. Uveitis

Uveitis is an inflammation of the uvea, and the uvea is made up of the ciliary body, the iris and choroid. Uveitis symptoms often come on suddenly and quickly get worse. Symptoms can include:

• Light sensitivities
• Eye redness
• Pain
• Blurry vision
• Decreased vision
• Floaters

6. Dry Eye

When a person doesn’t produce enough tears to lubricate and nourish the eye, he or she may develop a condition called dry eye. Dry eye usually affects both eyes and symptoms may include:

• Light sensitivities
• A scratchy or burning sensation
• Red eyes
• Difficulty wearing contact lens
• Eye fatigue

7. Thyroid Condition

Thyroid conditions may cause eye sensitivity. Graves disease is one of the examples. The disorder is caused by an abnormal antibody attack on the thyroid gland, and this abnormal antibody can also attack the eye tissues, causing swelling in the eye socket that pushes the eye forward, creating a protrusion of one or both eyes. Other symptoms could include:

• Eyes sensitive to light
• Red and/or swollen eyes
• Blurry or double vision
• Impaired color vision
• Teary eyes and/or discomfort in one or both eyes
• Inflammation, and/or reduced eye movement

8. Diabetes

People who have diabetes can have light sensitive eyes resulting from the damage to the blood vessels of the tissue at the back of the eye (retina). As the condition progresses, other symptoms may include:

• Cloudy or blurred vision
• Impaired color vision (faded or yellowish)
• Increased glare or halo effect around lights
• Poor vision at night
• Double or multiple vision in one eye
• Frequent adjustments in eyeglass or contact lens prescriptions

Note: Some medications such as quinine, tetracycline, and doxycycline may also cause light sensitivity.

Treatment for Light Sensitivity

The best way to treat light sensitivities is to identify and treat the underlying causes. Once the underlying condition is treated, the photophobia usually disappears. If medications are causing the problem, consult your healthcare provider about discontinuing or replacing the medication. People who have a lighter colored iris should avoid the bright sunlight and any other sources of light that trigger their symptoms. Wearing wide-brimmed hats along with a good pair of sunglasses with ultraviolet (UV) protection, or photochromic lenses that block 100 percent of the sun's UV rays can be effective. You may also want to consider polarized sunglasses that protect against glare from reflective surfaces. In severe conditions, consider wearing prosthetic contact lenses that can reduce the amount of light that enters your eyes.