Nebulization is only a form of drug delivery, not a treatment in itself. Whether and what side effects occur with nebulization is related to the medication used. In theory, any drug has certain side effects, and the probability of occurrence is highly related to the length of time and intensity of use. The side effects of each drug are different, for example, bronchodilators are mainly β2 agonists, which can easily cause hand tremors with long-term use. Glucocorticoids, long-term nebulized inhalation therapy, can cause fungal infections in the oropharynx. Phlegmolytic drug acetylcysteine tends to cause symptoms of nausea and vomiting. And antibiotics long-term nebulization, easy to cause drug resistance as well as secondary infection. Therefore, nebulization treatment should strictly comply with the norms, rather than random nebulization.