It is normal for the eyes to be sensitive to the sudden brightness of
light, such as when you turn on a light during the night or go out into the sun
after being indoors. This usually goes away within a few minutes.
Photophobia is an abnormal sensitivity to artificial or natural
light. Mild sensitivity may mean that wearing sunglasses in certain lighting
helps your eyes feel better. More severe sensitivity may mean that you avoid
light as much as possible and keep your eyes covered in any lighted
Common causes of photophobia include inflammation of the iris, the
cornea, or the conjunctiva (conjunctivitis, or pinkeye).
New sensitivity to light that is painful and causes you to close your
eyes or to need sunglasses even when you are indoors may be a sign of a serious
condition. It may mean a problem or inflammation in the muscle that
controls the movement of the pupil (iritis). This usually requires evaluation
by your doctor.