Photophobia, or light sensitivity, can make sunlight, indoor lighting, headlights, screens, or glare feel uncomfortable, overwhelming, or even painful. Light sensitivity is not a disease by itself. It is a symptom that can point to dry eye, cataracts, migraines, eye inflammation, medication side effects, or another vision or health concern.
In sunny Arizona, many people blame bright light alone. But when light sensitivity starts affecting driving, reading, screen time, work, or time outdoors, your eyes may need a closer look. Barnet Dulaney Perkins Eye Center can help identify the cause of your sensitivity and guide you toward the right next step.
How Your Eyes Process Light When Sensitivity Happens
Light sensitivity (also known as photophobia) is a common condition that can cause discomfort or even pain when your eyes are exposed to light. While light is essential for vision, the visual system relies on a precise and coordinated process to interpret it. When something interferes with that process, even normal indoor lighting or sunlight can become overwhelming.
Before exploring what causes photophobia and how it’s treated, it helps to understand how your eyes normally process light and why disruptions can lead to sensitivity.
How Your Eyes Use Light (Step by Step)
Every time you step into the bright sun, your eyes complete this process in milliseconds:
- Light reflects off objects and enters the front of the eye
- It passes through a thin tear film that protects and nourishes the eye
- The cornea begins focusing the light
- Light moves through the aqueous humor and enters the pupil, which adjusts to control light intake
- The lens fine-tunes focus for near or distant objects
- Light travels through the vitreous humor, a clear gel filling the eye
- The retina converts light into electrical signals
- These signals travel through the optic nerve to the brain
- The brain processes them into the images you see
Many structures are involved; light sensitivity can stem from problems anywhere along this pathway or from conditions outside the eye altogether.
What Causes Photophobia?
According to Medline Plus from the National Library of Medicine, some causes of sensitivity to light include:
- Eye inflammation
- Corneal abrasion or ulcer
- Wearing contact lenses for too long or lenses that fit poorly
- Eye infection, diseases, injury, or recovering from eye surgery
- Meningitis
- Migraine headaches
- Medications
Light Sensitivity, Migraines, and Brain-Related Conditions
Up to 80 percent of people who have photophobia experience a migraine along with the sensitivity to light. According to the American Migraine Foundation, light sensitivity is a symptom of migraines. Not all headaches that cause light sensitivity are migraines; individuals with tension and cluster headaches can also be sensitive to bright light.
If you experience chronic headaches due to light sensitivity, discuss your symptoms with a doctor as these may indicate a serious condition, including a brain injury or disease.
Tumors of the pituitary gland can also cause eye pain and headaches. In some cases, the tumor produces hormones that can cause a variety of symptoms, including headache. In other cases, tumors can grow and begin putting pressure on the surrounding areas in the brain and nerves, which can result in headaches and vision loss. Treatment depends on the symptoms; your doctor may recommend surgery or medication to reduce excess hormones.
Medications and the Sun: Why Some Drugs Heighten Light Sensitivity

Some photosensitizing medications include:
- Antihistamines
- Furosemide
- Non-steroidal, anti-Inflammatory drugs (NSAIDs)
- Oral and estrogen-based contraceptives
- Quinine
- Sulfonamides
- Tetracycline
- Tricyclic antidepressants
If you’re taking these medications and experiencing eye discomfort in sunlight, Barnet Dulaney Perkins eye doctors can help determine whether photophobia is medication-related or due to an eye condition.
Eye Conditions That Commonly Cause Light Sensitivity
The American Academy of Ophthalmology notes that photophobia may be associated with several eye conditions, including:
- Cataracts
- Corneal abrasion
- Conjunctivitis or pink eye
- Dry eye disease (very common in Arizona)
- Eye allergies
- Keratitis, which is also caused by corneal inflammation
- Uveitis, an inflammation of the eye
Because increased sensitivity to light is a symptom of many eye conditions, you should schedule an eye exam with your eye doctor as soon as you notice a marked increase in photophobia.
Coping With Light Sensitivity
If photophobia makes bright light uncomfortable, a few small changes may help reduce irritation while you wait for an eye exam or follow your doctor’s treatment plan.
Try these light sensitivity tips:
- Give your eyes a moment to adjust when moving between dark and bright spaces.
- Wear polarized sunglasses outdoors to reduce glare.
- Choose UV-protective sunglasses to help shield your eyes from ultraviolet light.
- Consider wraparound sunglasses if light enters from the sides.
- Adjust screen brightness and reduce harsh contrast when using phones or computers.
- Use artificial tears if your doctor has diagnosed dry eye.
- Avoid wearing contact lenses longer than recommended.
- Schedule an eye exam if symptoms worsen, return often, or affect daily activities.
These steps may improve comfort, but they do not replace diagnosis. If dry eye, cataracts, inflammation, migraine, or another condition is causing your symptoms, your eye doctor can recommend treatment based on the cause.
Find Relief From Light Sensitivity
Photophobia can turn normal light into a daily frustration, but you do not have to guess what is causing it. If Arizona sunlight, indoor lighting, headlights, or screens make your eyes uncomfortable, schedule an eye exam with Barnet Dulaney Perkins Eye Center. Our team can evaluate your symptoms, check for common causes like dry eye, cataracts, inflammation, or other eye conditions, and help you take the next step toward clearer, more comfortable vision.