Why Would One Eye Pupil Be Bigger Than the Other?

The most important thing to do is visit a doctor to know the underlying cause of the unequal size of pupils. In some people, this change can be accompanied by pain, vision loss, double vision, drooping eyelid and headache. Physical examination is necessary should a person have any of these symptoms. Treatment for the unequal pupil size is not necessary, but the underlying cause may need treatment.