What Causes Light Sensitivity? A Complete Guide to Photophobia Causes

Why Am I Sensitive to Light?

Light sensitivity (photophobia) occurs when the nerve pathways between your eyes and brain overreact to light stimuli. Understanding the cause is the first step toward finding effective treatment.

Eye-Related Causes

The most common causes of light sensitivity originate in the eyes themselves:

Corneal Surface Problems

• Dry eye syndrome — the #1 eye-related cause of photophobia
• Corneal abrasions — scratches cause acute, severe light sensitivity
• Keratitis — corneal infection or inflammation
• Contact lens problems — overwear, poor fit, or infection

Internal Eye Inflammation

• Uveitis — inflammation of the uveal tract
• Iritis — inflammation specifically of the iris
• Cyclitis — inflammation of the ciliary body

Structural Eye Issues

• Cataracts — increased light scatter through cloudy lens
• Glaucoma — particularly angle-closure glaucoma
• Albinism — reduced iris pigment allows excess light entry

Neurological Causes

Many neurological conditions affect how the brain processes light signals:

• Migraine — the most common neurological cause (80-90% of migraine sufferers)
• Concussion / TBI — light sensitivity often persists weeks to months
• Meningitis / encephalitis — photophobia is a hallmark symptom
• Multiple sclerosis — optic neuritis causes visual sensitivity
• Trigeminal neuralgia — facial nerve pain linked to photophobia

Browse all conditions that cause light sensitivity →

Medication-Induced Causes

Over 100 medications list photosensitivity as a side effect:

• Antibiotics: Doxycycline, tetracycline, ciprofloxacin
• Retinoids: Isotretinoin (Accutane), tretinoin
• Psychiatric medications: Certain SSRIs, antipsychotics
• Cardiac medications: Amiodarone, hydrochlorothiazide
• NSAIDs: Ibuprofen, naproxen (rare)

Full list of photosensitizing medications →

Environmental and Lifestyle Causes

• Prolonged screen use — digital eye strain
• Fluorescent lighting — flicker and spectral quality
• Sudden brightness changes — moving from dark to bright environments
• Sleep deprivation — increases overall sensory sensitivity
• Dehydration — can worsen dry eye and sensitivity

Psychological Causes

• Anxiety disorders — heightened sensory processing
• Depression — altered pain and light perception
• PTSD — hypervigilance includes light sensitivity
• Stress — can trigger or worsen existing photophobia

When Light Sensitivity Is an Emergency

Seek immediate medical care if photophobia occurs with:

• Severe headache + stiff neck + fever (meningitis)
• Sudden vision loss
• Severe eye pain with nausea/vomiting
• After head trauma or eye injury

Next Steps

If you’re experiencing unexplained light sensitivity, start by seeing your primary care doctor or an ophthalmologist. They can help identify the underlying cause and recommend appropriate treatment.

Explore treatment options →

Sources

1. Digre KB, Brennan KC. “Shedding light on photophobia.” J Neuro-Ophthalmol. 2012;32(1):68-81.
2. Katz BJ, Digre KB. “Diagnosis, pathophysiology, and treatment of photophobia.” Survey of Ophthalmology. 2016;61(4):466-477.