? Children’s nebulized drugs are specially used for nebulization and have a unique mechanism and effect in the production process. Through the nebulization machine to make the drug output in the form of aerosol, the drug particles can reach 1-5 microns in diameter, is by the baby wearing a mask, with the breathing airflow of drug particles directly into the lungs, in the trachea and lung local effect; drug directly with the airway surface mucosal epithelium and play the effect. From the principle of nebulizer work we can see that it is different from injectable drugs, which means that injectable drugs cannot be used for nebulized inhalation. There are several types of nebulized inhalation drugs in common use: a. Inhalation drugs for symptom control Inhalation bronchodilators (representative drugs include terbutaline, salbutamol, ipratropium bromide), which can quickly relieve bronchospasm and quickly reduce the symptoms of cough, wheezing, chest tightness, etc. in children. Second, inhaled drugs to control inflammation Inhaled glucocorticoids work to reduce airway inflammation and effectively control the baby’s wheezing and coughing symptoms. The hormones can play an anti-inflammatory role and can effectively reduce the dosage of systemic hormones, decrease the hospitalization rate and reduce the time the child misses school. Third, inhalation drugs for clearing airway secretions Inhalation acetylcysteine; also known as expectorants by the people. Expectorants work by regulating mucus secretion in the airways of children, increasing cilia oscillation and making it easier to cough up sputum. Nebulized inhalation drugs do not need to go through the blood circulation, and the amount of inhaled drugs is smaller compared to oral and infusion doses, so they are naturally safer. Other intravenous hormones (e.g. dexamethasone), antibiotics (e.g. gentamicin), antiviral drugs (ribavirin), expectorant drugs (tranylcypromine), and various herbal preparations are not suitable for nebulized inhalation.