When the dark circle in the center of your eye is larger than normal Dilated pupils (mydriasis) can happen for many reasons, such as a normal response to light, medication or drug use, eye exams ...

is a condition in which the pupil in one of your eyes spontaneously dilates. It can stay dilated for just a few minutes or can go for days before returning to its normal size, Mackay says.

Medically reviewed by Diana Apetauerova, MD Pupils, the dark circles in your eyes, are usually equal in size. Unequal pupils ...