Sudden Light Sensitivity: Causes, Treatments, and Prevention

1. Migraine

Migraines are one of the most common causes of light sensitivity. A migraine is a condition involving the brain that is often characterised by headaches that are severe in nature and may also involve other symptoms such as nausea depending on the type of migraine, according to Health Direct. One of the most common symptoms of migraines is sensitivity to light. Light sensitivity and migraines are so closely linked that light sensitivity is a key criterion in diagnosing migraines, according to the American Migraine Foundation. Those who have light sensitivity during a migraine attack may find that light causes discomfort or pain in the eye and worsens the migraine. Moving to a dark room or wearing sunglasses during a migraine attack to limit the amount of light hitting the eye may provide some relief.

2. Inflamed Eyelid (Blepharitis)

An inflamed eyelid, also known as blepharitis, may cause light sensitivity. Inflammation of the eyelids or blepharitis is an eye condition in which the eyelids become inflamed, irritated, red or swollen, often caused by a build-up of bacteria. Symptoms of blepharitis include teary eyes, crusty eyes and light sensitivity.

3. Scratched Eye

An eye scratch, also known as a corneal abrasion, may cause sudden sensitivity to light. A scratched eye refers to an abrasion on the surface of the eye, usually on the cornea, the top, clear layer at the front of the eye. According to the National Eye Institute, the cornea helps light entering the eye focus onto the retina properly. An abrasion to the cornea may make the eye more sensitive to light and may cause other symptoms such as discomfort or pain.

4. Conjunctivitis (Pink Eye)

Conjunctivitis may cause sensitivity to light as a result of the infection or inflammation caused by this condition. If there is severe sensitivity to light, it is important to see a doctor as soon as possible. Conjunctivitis, also known as pink eye, is an eye condition in which the whites of the eyes, known as the sclera, become inflamed, as a result of infection or allergies. There are several types of conjunctivitis including bacterial conjunctivitis, viral conjunctivitis and allergic conjunctivitis.

5. Chronic Dry Eyes

Chronic dry eyes is an eye condition that may cause light sensitivity. Chronic dry eyes or dry eyes disease is an eye condition in which the eyes do not produce enough tears and are unable to provide adequate lubrication to the surface of the eyes, leaving the eyes dry. Light sensitivity may present as a symptom of dry eyes.

7. Scleritis

Scleritis refers to inflammation of the sclera, the white parts of the eye, and may cause sensitivity to light. The sclera is the white part of the eye that helps maintain the shape of the eye and protects it against injury. Scleritis is an inflammation of the sclera and can be caused by a range of issues from eye infections to underlying health conditions such as rheumatoid arthritis. Scleritis can cause symptoms including light sensitivity, pain and tenderness in the eye, according to the American Academy of Ophthalmology.

8. Keratitis (Corneal Inflammation)

Keratitis, also known as corneal inflammation, refers to an inflammation of the cornea part of the eye, a symptom of which may be light sensitivity. The cornea is the clear window at the front of the eye that lets light in. Keratitis can be caused by an infection such as bacterial keratitis or can have a non-infectious cause such as an eye injury or vitamin A deficiency, according to the Cleveland Clinic. Keratitis can cause symptoms including light sensitivity, watery eyes and eye pain.

9. Eye Dilation

Eye dilation may cause light sensitivity as the pupil is widened during eye dilation and will let more light in than usual. The pupil is the black circle in the centre of the eye that controls light entering the eye. Eye dilation is the process of the pupils becoming dilated or widened by eye drops, as part of an eye test to assist an optometrist in seeing the deeper structures of the eye. Eye dilation may cause light sensitivity as dilation increases the size of the pupil, allowing more light into the eye, according to the Bright Focus Foundation. Eye dilation from a dilated eye exam may last for several hours.

1. Take a Rest

Taking a rest is a great way to treat light sensitivity at home as it allows the eyes to have a break from irritating light by closing the eyes. For full benefits, make sure to rest in a dark room where possible to escape light causing the sensitivity. You can also use a warm or cold compress over the eyes to further relax and treat discomfort or pain.

2. Use Eye Drops

Eye drops may be used to treat light sensitivity if this eye symptom is caused by corneal abrasions, conjunctivitis or scleritis. According to Drugs.com, there are different types of eye drops that can be used to treat light sensitivity, also known as photophobia, depending on the causes. These eye drops include artificial tears for dry eyes, antibiotics for bacterial infections, steroids for eye swelling, antivirals for viral infections and antifungals for fungal infections.

3. Wear Sunglasses

For people who have sensitivity to light, wearing sunglasses can help with pain and discomfort by dimming light entering the eye. Sunglasses can be tint, to protect the eyes from UV or there are polarised sunglasses, to protect the eyes from glare. However, make sure not to wear sunglasses indoors as a study published in the Elsevier Survey of Ophthalmology in 2015 found that this can aggravate a person’s sensitivity to light as they are dark adapting their retinas.

What are Other Serious Reasons for Sudden Light Sensitivity?

Sudden light sensitivity can be caused by serious medical conditions including herpes keratitis, encephalitis and meningitis. If you have the symptoms of any of the above symptoms, it is important to seek immediate medical attention. The serious causes of sudden light sensitivity are listed below.

• Herpes Keratitis: Herpes keratitis, also known as eye herpes, is an eye infection caused by the HSV-1 virus. Symptoms of Herpes keratitis can be a serious condition and lead to blindness if not treated.
• Encephalitis: Encephalitis is a serious condition in which the brain is inflamed. Symptoms of encephalitis can include confusion, seizures, changes in personality, speech or movement, weakness, and may also include light sensitivity according to Health Direct. It is essential to seek medical attention if you have symptoms of encephalitis as it can lead to permanent brain damage.
• Meningitis: Meningitis is a serious medical condition involving the inflammation of the tissue and membranes surrounding the brain and spinal cord. According to the World Health Organisation, meningitis can be fatal and it is important to seek immediate medical attention if you have symptoms of meningitis. According to the NHS, symptoms of meningitis can include high fever, cold hands, confusion, vomiting, a stiff neck, seizures, a rash and sensitivity to bright lights.

What are the Possible Effects If Light Sensitivity is Not Treated Immediately?

The effects of not treating light sensitivity depend on the underlying cause of light sensitivity. It is important to treat conjunctivitis, which may cause light sensitivity, as eye damage may be caused by chronic, untreated conjunctivitis, according to Mount Sinai Health System.

Can Non-Prescription Glasses Prevent Sudden Light Sensitivity?

Non-prescription glasses may help to prevent eye issues that may cause light sensitivity, such as eye injuries. Injuries to the eye, such as corneal abrasions, may cause light sensitivity. Non-prescription protective glasses may help prevent eye injuries during activities such as gardening or working in conditions where there is debris. Non-prescription glasses such as sunglasses can be useful in the management of light sensitivity as they can shield the eyes from bright lights.