Light Sensitivity (Photophobia): Causes and When to Worry

Light sensitivity, or photophobia, means your eyes are more sensitive to light than usual, so ordinary brightness feels uncomfortable or even painful. It is a symptom with many possible causes. The cause can be on the surface of the eye, as with dry eye or a scratched cornea; inside the eye, as with uveitis; or outside the eye, as with migraine. New light sensitivity that lingers deserves an eye exam. If it starts suddenly with eye pain, redness or blurred vision, get a same-day visit (an emergency room when we're closed). If it comes with a sudden severe headache or sudden vision loss, call 911, and if it comes with fever, headache and a stiff neck, get emergency care right away.

Key takeaways

Light sensitivity has many possible causes, from dry eye or a scratched cornea to inflammation inside the eye (uveitis), a cataract or migraine.
Sudden light sensitivity with eye pain, a red eye or blurred vision needs a same-day exam, or an emergency room when we're closed.
Treatment targets the cause, such as prescription steroid drops for uveitis or a dry eye plan built from imaging of the eyelid oil glands.
Call 911 if light sensitivity comes with a sudden severe headache or sudden vision loss, and get emergency care right away for fever, headache and a stiff neck.

What causes sensitivity to light?

Eye causes include dry eye, a cataract, a scratched cornea, keratitis (an inflamed cornea) and uveitis, and the symptoms that come with the light sensitivity usually point to which one. Our eye symptoms guide sorts other complaints by urgency in the same way.

Cause	What else you may notice	How soon to be seen
Dry eye	A scratchy feeling, stinging or burning, red eyes, blurry vision	Book an exam
Cataract (a cloudy area in the lens of the eye)	Lamps, sunlight or headlights seem too bright; a halo around lights; faded colors	Book an exam
Corneal abrasion (a cut or scratch on the cornea, the clear front of the eye)	Pain that ranges from mild discomfort to intense stabbing; blurred vision; an eye that waters uncontrollably	Same day (emergency room when we're closed)
Keratitis (inflammation of the cornea, which can be an infection)	Irritated, red eyes; worsening pain; sudden blurry vision; unusually watery eyes or discharge	Same day (emergency room when we're closed)
Uveitis (inflammation inside the eye)	Eye pain, red eyes, blurry vision, floaters; symptoms usually start suddenly	Same day (emergency room when we're closed)

Contact lenses raise the risk of keratitis when they are not worn, cleaned and stored as directed, and light sensitivity is one of its symptoms. If you wear lenses and an eye turns red, painful or light-sensitive, take the lenses out and call us right away for a same-day exam, or go to an emergency room when we're closed; the CDC's advice is to remove the lenses and call your eye doctor immediately.

For a few hours after a dilated eye exam, your vision may be blurry and your eyes sensitive to light, and sunglasses help.

Eye surgery can do it too. After cataract surgery, the eye may feel a bit itchy or uncomfortable and sensitive to light and touch. After LASIK, the FDA tells patients they may notice sensitivity to light, glare, starbursts or haloes around lights. We see patients before and after both operations through surgery co-management.

Can light sensitivity come from outside the eye?

Yes. Migraine is the familiar example: people with migraine may also be sensitive to light, noise and smells, and some first see an aura, usually a visual one such as dots, zigzags or sparks.

A head injury can cause it too. Being bothered by light or noise is one of the listed symptoms of a concussion.

Meningitis is the cause that cannot wait. It is an inflammation (swelling) of the lining of the brain and spinal cord. Its common symptoms are fever, headache and a stiff neck, and photophobia is on the list with nausea, vomiting and confusion.

When is light sensitivity an emergency?

Call 911 if it comes with a sudden severe headache or sudden vision loss, which can be signs of a stroke; fever with a headache and a stiff neck needs emergency care right away, and a cut to the eye needs an emergency room. Otherwise, light sensitivity that starts suddenly with eye pain, a red eye or blurred vision needs a same-day exam, and severe eye pain, an eye injury or a red, painful eye in a contact lens wearer needs a call to us right away; when we're closed, go to an emergency room for any of these.

Call 911 or go to an emergency room for

Light sensitivity with fever, headache and a stiff neck. The CDC calls bacterial meningitis a medical emergency.
A sudden, severe headache with no known cause, sudden loss of vision in one or both eyes (even if it comes back), or sudden double vision. Each can be a sign of a stroke, so call 911 even if the symptoms go away.
A headache that gets worse and does not go away after a head injury, repeated vomiting, or one pupil larger than the other.
A cut to the eye, or an object that has pierced it. Go to the emergency room without rinsing the eye or trying to remove anything, and protect it without pressing on it.

Call us right away for

Severe eye pain with nausea, a headache, or halos or colored rings around lights. That can be acute angle-closure glaucoma, an emergency in which severe vision loss can occur quickly. When we're closed, go to an emergency room; going straight to one is also right.
Something stuck in your eye. Don't rub it. Call and come straight in, because our doctors remove these in the office, and use an emergency room only when we're closed.
A red, painful eye in a contact lens wearer, or a white spot on the cornea. Take the lenses out and call us right away for a same-day exam; when we're closed, go to an emergency room.
Any injury to the eye, including pain and light sensitivity after something scratched or hit it. When we're closed, go to an emergency room.

Get a same-day eye exam

Light sensitivity that starts suddenly, with eye pain, a red eye or blurred vision, needs an exam the same day, or an emergency room when we're closed. These are the patterns of uveitis, keratitis or an injured cornea, and the National Eye Institute advises seeing an eye doctor right away for uveitis symptoms. For a scratched cornea, the American Optometric Association says a doctor of optometry should make the diagnosis and notes that most emergency rooms do not have the equipment to diagnose superficial eye injuries, so it recommends one only when it is the only care available.

We hold same-day urgent appointments during office hours, Monday 10 to 5 and Tuesday to Friday 8 to 5; call 310-828-2010. When we're closed, including weekends, don't wait for us to open: go to an emergency room for light sensitivity that starts suddenly with eye pain, a red eye or blurred vision, after an eye injury, or for a red, painful eye if you wear contact lenses. The National Eye Institute lists intense eye pain, blurry vision and very red, watery eyes among the reasons to go to the eye doctor or the emergency room.

How do you treat light sensitivity?

You treat whatever is causing it. Uveitis is most often treated with prescription eye drops, and steroids are the medicines that calm the inflammation. An infection of the cornea needs an eye doctor right away (an emergency room when we're closed), which is why the CDC tells lens wearers with these symptoms to call immediately. Dry eye needs a longer plan, which is the work of our dry eye program.

That plan starts with imaging of the meibomian glands, the oil glands along the edges of the eyelids. Depending on what the imaging shows, treatment can include prescription drops; IPL (intense pulsed light), which uses gentle pulses of light to melt thickened oils and calm inflammation along the lids; or punctal plugs that keep your own tears on the eye longer.

New or painful light sensitivity needs an exam to find the cause. For time outdoors, our guide to UV protection and sunglasses explains what a good pair needs.

What if the iris lets in too much light?

Some light sensitivity starts with the iris, the colored part of the eye. In aniridia, part or all of the iris is missing, and people with it often have increased sensitivity to light. It is rare, occurring in 1 in 40,000 to 100,000 newborns worldwide.

For eyes like these we fit prosthetic soft contact lenses with a custom-printed iris. The printed iris blocks excess light much as a natural iris would, and its color, pattern and pupil size are matched to your other eye in the office. We also fit them for a gap in the iris (coloboma), for albinism, and for a pupil left fixed wide open after an injury. If the eye sees, your prescription can be built into the lens.

How we check light sensitivity at Cohenmehr Optometry

At Cohenmehr Optometry, the center of the visit is the slit lamp, a microscope that shows the cornea and the front of the eye in detail. A drop of dye makes scratches and sores on the cornea visible. We check eye pressure and dilate the pupils when your symptoms call for it.

If the surface looks dry, the dry eye evaluation adds a test of how stable your tear film is. When the cause needs a specialist, we coordinate the referral. If your eyes turn out to be healthy, the cause more likely lies outside the eye, and migraine and other possibilities are worth taking up with your physician.

Questions patients ask

What is iritis?

Iritis is another name for anterior uveitis, an inflammation of the middle layer of the eye. It causes a red, sore and inflamed eye, blurred vision and sensitivity to light. Treatment uses prescription drops that dilate the pupils together with anti-inflammatory medicine, and it takes several days or, in some cases, several weeks. Left untreated, it can lead to glaucoma, cataract or swelling of the retina and permanent vision loss, so we see it the same day; when we're closed, go to an emergency room. Our uveitis page goes deeper.

Do sunglasses need UV protection?

Yes. The American Optometric Association says sunglasses should block out 100% of both UV-A and UV-B radiation, because the longer your eyes are exposed to the sun's radiation, the greater the risk of cataracts, eye cancer, pterygium (surfer's eye) or macular degeneration later in life. Its checklist also calls for lenses that screen out 75 to 90% of visible light, gray lenses for proper color recognition, and lenses free of distortion. Our UV protection and sunglasses guide covers choosing a pair.

What are the symptoms of UV eye damage?

Short term, too much ultraviolet light can cause photokeratitis, which the American Optometric Association likens to a sunburn of the eye. It can be painful, with red eyes, a gritty feeling as if something is in the eye, extreme sensitivity to light and heavy tearing. These symptoms are usually temporary and rarely cause permanent damage. The sun isn't the only source: welding machines, tanning beds and lasers give off UV light too. A painful, light-sensitive eye still deserves a same-day visit, or an emergency room when we're closed.

What are some eye health tips?

The CDC's nine ways to protect your vision include regular comprehensive dilated eye exams and knowing your family's eye health history, since some eye conditions are hereditary. The list also covers eating dark leafy greens such as spinach or kale, wearing sunglasses that block ultraviolet light, wearing protective eyewear for sports and projects around the home, and quitting smoking. If you wear contacts, wash your hands before taking them out and clean the lenses properly to avoid infection.

Sources

Written by

Dr. Kevin Cohenmehr, OD

Medical eye care: glaucoma, diabetic eye exams, macular degeneration and eye infections, plus vision therapy for children. A graduate of UCLA and SUNY College of Optometry.

About Dr. Kevin →

Light Sensitivity (Photophobia): What Causes It and When to Worry