If your baby has a persistent cough, look for symptoms of nose rubbing. If there is, it may be a cough caused by rhinitis, you can spray the nose with Fosfomycin, as well as can use cyproheptadine, ketotifen anti-allergy, reduce airway sensitivity. If necessary, you can go to the hospital for routine blood tests, Mycoplasma pneumoniae antibodies and chest X-ray to see whether the symptoms are caused by bronchitis or bronchopneumonia with respiratory tract infection. If it is a bacterial infection, you can take amoxicillin clavulanate potassium anti-infection. If it is Mycoplasma pneumoniae infection, you can take erythromycin or azithromycin for anti-infection treatment, the general course of treatment is about 2-3 weeks, as well as to take aminoglutethimide oral solution to resolve sputum, to take budesonide and terbutaline for nebulization and other symptomatic treatment.