The common causes of infant tearing are as follows: 1. The tear ducts of newborn infants are thin and not completely open, at this time there is an increase in physiological tearing, which usually lasts 1-2 weeks and will recover. Many infants in 1 month will have a transient increase in tearing, will gradually ease, no special treatment; 2, 1 month after the baby will also appear more tearing, in addition to the tear duct is thin, there may be residual film nasolacrimal duct. At this time, you can slightly massage to relieve the symptoms. More than 95% of infants will be relieved gradually on their own; 3. Some infants have thicker residual membranes, resulting in poor tear drainage and increased lacrimation and increased eye stools. Infants above 4 months of age may consider tear duct flushing to clarify the degree of blockage. If the lacrimal duct is clear when flushed, but tears still flow, it is necessary to rule out the occurrence of inverted eyelashes and the presence of allergies at this time. If the infant develops sneezing, runny nose, and a rhinitis body, it may be related to the nasal cavity and a nasal examination should be performed.