Trichiasis can cause the eyes to tear. Patients with trichiasis exhibit significant tearing symptoms because the cornea is rich in nerve endings and is very sensitive to foreign stimuli. In trichiasis, the eyelashes poke and irritate the cornea, thus stimulating the nerve endings and causing reflex tearing. Therefore, patients with trichiasis should be treated promptly to avoid irreversible damage to the cornea, such as scars or corneal ulcers. For minor trichiasis, local electrolysis can be used to destroy the hair follicles so they no longer grow; for more severe cases, it is recommended to visit a hospital for surgical correction of the trichiasis.