Tearing

Tearing is the flow of tears that occurs when tear production increases and there is a disturbance in their drainage through tear ducts. Normally, the tear glands produce about 1 ml of tears per day. This amount is enough to moisten the eye, and the remaining unevaporated residue drains through tear ducts into the nose. Excess tears occur due to emotions, yawning, vomiting, sneezing. Tear production intensifies when the endings of the trigeminal nerve in the eye are irritated (e.g., foreign body in the eye), or when the optic nerve is irritated (e.g., glaring light). Tearing occurs when there are mechanical obstacles preventing tears from draining, leading to constant tearing even though tear production does not increase.

Source | Author Doctor Nikas Samuolis, reviewed by Prof. Virginijus Šapoka | Vilnius University | Faculty of Medicine | Head of the Department of Internal Medicine, Family Medicine, and Oncology