The common cause of crooked mouth caused by fans is facial nerve palsy, also known as facial neuritis, due to local cold and viral infection, patients mainly manifest as incomplete closure of one eyelid, loss of one side of the frontal line, drooling and so on. In the case of facial neuritis, the patient should pay attention to rest, eat lightly, keep the appropriate temperature, do not use cold water to wash the face, wear a mask when going out, use warm towels to apply local heat to improve local blood circulation, often exercise whistling, cheek puffs and other actions, rinse the mouth after meals, remove residual food from the teeth and cheeks. Facial neuritis in the drug treatment, mainly choose vitamin B1, vitamin B12, methylcobalamin and other nerve-nourishing drugs, can also choose glucocorticoids, mannitol and other drugs to reduce facial neuritis edema, recovery patients can be combined with acupuncture, massage. With regular systemic treatment, most patients can fully recover in 1-3 months.