There are usually no magic tricks to relieve children from coughing up phlegm, and scientific and professional methods are needed to expel phlegm. For example, back patting and postural drainage can be used to help expel phlegm, and dietary regimen, keeping indoor air circulation, inhalation of water vapor, nebulized inhalation and oral medication can also be used to promote phlegm expulsion. If phlegm still cannot be discharged and a large amount of phlegm accumulates in the throat, you can go to the hospital to take negative pressure suction to discharge phlegm.1. Patting the back: usually done in between coughing, with five fingers slightly flexed, clenched into an empty fist, gently patting the child’s back, lying to the left when patting the left side, lying to the right when patting the right side, alternating sides. Patting the back can help the lungs and bronchi to drain and discharge phlegm to the large airways, promote blood circulation to the heart and lungs, facilitate the absorption of inflammation, and enable the disease to heal early. Patting the back should be done from bottom to top and from outside to inside, 2-3 times a day, for about 5 minutes each time; 2, position drainage: if the lesion is upper lobe of lung, interlobe, it can be drained in sitting position or semi-recumbent position, if the lesion is other parts, it can be drained in head-low position and supine position; 3, diet regulation: if you have phlegm and can’t cough, you can drink more water, which can dilute the phlegm, the temperature of water should be around 40℃, you can also eat to clear lung and dissolve phlegm food, such as pear, has a better effect of resolving phlegm; 4, keep indoor air circulation: the room should be frequently opened and ventilated, about 20 minutes each time, the temperature and humidity in fresh air is more suitable, which can reduce the generation of phlegm; 5, inhale water vapor: pour boiling water into a jar or tea cup, make the child’s mouth and nose to the water vapor, which can make the phlegm thin, which is conducive to coughing out phlegm, but be careful scalding; humidifier, etc. can be used when available.6. Nebulized inhalation: if phlegm-forming drugs such as Ambroxol can be used for nebulized inhalation, it can effectively dilute phlegm and promote phlegm discharge.7. Oral drugs: phlegm-forming drugs can be taken orally, such as Jin Zhen oral solution and Ambroxol hydrochloride oral solution, which have better phlegm-forming effects. If bacterial or mycoplasma infection is indicated, sensitive drugs can be used for treatment, such as clarithromycin tablets; 8. Negative pressure aspiration: when the above methods are ineffective, children can be brought to the hospital for negative pressure aspiration by professional medical personnel. The pressure of negative pressure aspiration should not be too high to avoid damaging the respiratory mucosa, and should not exceed 15 seconds each time.