Pupil constriction

Pupil constriction is a symptom in which the pupils of the eyes become smaller than usual. It is often caused by exposure to bright light, or by certain medications. It can also be caused by an underlying medical condition, such as an infection or an eye injury. The constriction of the pupils is usually accompanied by a decrease in the amount of light entering the eyes. It can cause difficulty with vision, and may lead to headaches and dizziness. In some cases, pupil constriction can be a sign of a serious medical condition, such as a stroke or brain tumor.