Cough is one of the most common symptoms seen in children of all ages at the time of consultation. Chronic cough is one of the common clinical problems in pediatrics and the most common clinical manifestation of respiratory diseases. It may be caused only by recurrent upper respiratory tract infections, but it may also be one of the early manifestations of some serious underlying diseases. Detailed history taking, careful physical examination and some necessary laboratory and chest imaging tests must be performed to clarify the etiology and treat accordingly. I. Definition of chronic cough Children with cough as the main complaint account for more than 50% of outpatient visits. A cough of about 1 week is quite common in common upper respiratory tract infections, but a persistent or recurrent cough of more than 3 weeks (more than 4 weeks is predominant in chronic cough clinics) should attract the attention of clinicians and require some necessary tests to clarify the cause of the long-term cough and treat it accordingly. 2. Common causes and clinical characteristics of chronic cough 1. postnasal drip syndrome (posmasaldrip, PND): Children often present with itchy, painful, coughing larynx, and the cough is often more pronounced before and after sleep. The sputum is mucous in nature. Some children have a feeling of flowing secretions in the larynx and often have repeated throat-clearing movements due to discomfort in the throat. Secretions and nodular lymphoid follicular hyperplasia are seen in the posterior pharyngeal wall. 2. Reactive respiratory disease: It is a clinical syndrome dominated by recurrent coughing or wheezing episodes with complex causes and great variation in the duration and degree of cough, and is one of the common causes of chronic cough. The disease has a certain genetic predisposition and manifests clinically as a prolonged or recurrent coughing process, which is heavier in the early morning and late at night, and worsens during the day after strenuous or crying episodes, sometimes with wheezing episodes. Antibiotic therapy is often ineffective, while it responds better to bronchodilators. Factors causing hyper-reactive respiratory tract, in addition to allergies and viral infections, some non-specific stimuli, such as passive smoking, home furnishing Juan pollution, etc.; some intrauterine lung infections, as well as pulmonary dysplasia, prematurity and other lung development abnormalities; these children with some factors triggered, cough will last longer. 3. Inhalation syndrome Mainly refers to repeated, small amounts of aspiration of liquid (stomach acid, milk or upper respiratory secretions, etc.) or solid material (stomach contents) from the respiratory tract, which causes chronic coughing due to long-term irritation of the respiratory tract. Other etiologies that can cause recurrent aspiration include coma, neuromuscular disease, laryngeal cleft, tracheoesophageal fistula, etc. Due to swallowing dysfunction or incoordination, this causes aspiration of oral secretions or food, resulting in recurrent long-term infection of the respiratory tract or lungs. 4, chronic migratory or focal infections such as Mycoplasma pneumoniae and Chlamydia pneumoniae infections in infancy and early childhood, which can easily lead to recurrent coughing and even wheezing episodes X-ray chest films showing interstitial changes. Nowadays, there are many children with Mycoplasma pneumoniae infections causing chronic cough, which should be taken seriously. Mycobacterium tuberculosis infection of the lungs, especially primary infection with atypical clinical manifestations and chronic cough as the main manifestation, should be promptly treated with frontal and lateral chest radiographs and pure protein derivative (PPD) skin tests of Mycobacterium tuberculosis. Cough symptoms caused by Mycobacterium pertussis and Mycobacterium pertussis-like infections will continue for some time. In addition, focal infectious lesions such as chronic tonsillitis, bronchiectasis from various causes, and lung abscess can be the cause of chronic cough. 5. Psychogenic or habitual cough With the increase in learning pressure or the long-term stimulation of some chronic lesions (e.g. pharyngitis, severe chronic tonsillitis), some children develop a psychogenic or habitual cough cough that is often intense and persistent with exaggerated movements, but disappears after changing the environment or attention and after the person goes to sleep. The diagnosis of this disease must exclude other causes of chronic cough . III. Treatment of chronic cough: The key to successful treatment of cough is a clear diagnosis and treatment of its cause. In conclusion, chronic cough is a common pediatric symptom, but the causes of chronic cough are extremely complex. To obtain good treatment results, the cause and possible mechanisms must first be clarified, followed by targeted treatment. The above is the Western medicine aspect, but the following is the Chinese medicine aspect of the physical and etiological factors of children with cough, and the dialectical identification and treatment! The following are some of the causes: Qi and Yin deficiency, food accumulation, lung heat, stubborn phlegm in the lungs, etc. Qi deficiency, unfavorable nose, etc. In clinical practice, we often see children with recurrent colds, coughs with phlegm, and even wheezing, often hanging water, taking medicine and the effect is not good. Most of these children are suffering from qi and yin deficiency, food accumulation and internal heat, such as qi deficiency is often a little exercise that is sweating more, easily tired, some nose is not good, some exercise more cough, often easy to catch a cold. Yin deficiency is sweating a lot after sleeping, the heart of the hands and feet is hot, easily stirring and cold, and even restlessness at night, dreaming a lot, dreaming. Food accumulation and lung fever is caused by improper feeding and care of the parents, resulting in the child’s diet being paranoid or drinking too much milk, resulting in the child’s tendency to sleep prone, or in severe cases, to sleep with his buttocks puckered, and the child has an odor in his mouth and is prone to tonsillitis, fever, dry stools, etc. In the case of stubborn phlegm in the lungs, it is due to physical abnormalities (such as asthma, allergies, etc.), or after illness, or after discharge from the hospital, there is always phlegm in the lungs that is difficult to clear, and in severe cases, there is a sound or “roar” in the throat, such as improper diet, or coughing for a long time after a cold. The above conditions, such as qi deficiency or yin deficiency or food stagnation, can occur singly or in combination. Therefore, in the treatment of cough in children, it is particularly important to identify the child’s body type and to treat the disease with evidence. The main distinction between coughs with external sensations and coughs with internal injuries is made. Treatment principles The treatment of this disease should distinguish between the true and false state of evil and external and internal injuries. If the cough is due to an external sensation, it should be classified as wind-cold or wind-heat cough, and only on this basis can Chinese medicine or proprietary Chinese medicine be used. If you do not distinguish between wind-cold coughs but use cold herbs or Chinese medicines (most of the Chinese medicines used in pediatrics to stop coughs and treat colds are cold), you are adding insult to injury and delaying your condition. In the case of internal cough, it is necessary to distinguish between phlegm-heat cough, phlegm-damp cough, yin-deficiency cough, qi-deficiency cough, etc. In severe cases, there can be a combination of conditions, so it is especially important to differentiate the conditions in order to use medication. For example, some children with asthma often cough and catch a cold when they are not having an attack, some of them have a deficiency of qi and yin, and the accumulation of phlegm and phlegm is caused by food. It can even make the child’s physical development stop.