Saline cleaning of the nasal cavity has the following contraindications: First, try to avoid cleaning the nasal cavity during the acute attack of allergic rhinitis, because this time cleaning the nasal cavity is easy to induce the olfactory nerve of the mucosa of the nasal cavity, which leads to more severe sneezing in patients. It is also easy to cause saline choking into the trachea, which leads to discomfort. Second, if the patient has active bleeding in the nasal cavity, clinically it is best not to do nasal cleaning, it is easy to induce bleeding again. Third, if the children do not cooperate well, try not to clean, otherwise it is easy to lead to saline all swallowed into the stomach or choking into the trachea. Fourth, for some elderly patients, such as Alzheimer’s disease or swallowing function is particularly poor, without the ability to live on their own, try not to do nasal cleaning, also easy to induce patients to choke, the risk of aspiration. Clinically do nasal cleaning as much as possible to the saline temperature and body temperature to the same, avoid too cold, too hot, so as not to lead to nasal burns or easily induced by the patient to appear in the nasal cavity discomfort.