The most common reason for sudden tearing of the eyes is the entry of a foreign body into the eye, it is recommended to go to the hospital as soon as possible, so that the doctor can carefully examine the foreign body under the slit lamp, if there is a foreign body to remove the foreign body, and then according to the degree of damage to the eye to develop the next medication measures. In addition, if you stay up late for a long time, poor rest, lack of sleep, will also lead to the next day, the eyes suddenly tears can not open the situation, it is recommended to develop good habits, do not use the eyes for a long time close, especially a long time to look at the phone, play computer, etc.. In addition, some physical and chemical stimuli can also cause sudden tears, such as electrophthalmia, prolonged ultraviolet radiation may lead to diffuse corneal defects or clouding, causing electrophthalmia, in addition to exposure to formaldehyde, etc. can also lead to sudden tears in the eyes.