It refers to the infection of upper respiratory tract (nose, pharynx, tonsil), trachea, bronchus and lung caused by various bacteria, viruses, mycoplasma pneumoniae and chlamydia pneumoniae, which makes children cough at night. Specific manifestations are fever and cold, tracheitis symptoms (sore throat, burning, etc.), throat tonsillitis. There are also very few pathogens that cause obvious cough at night, such as whooping cough, pertussis-like cough, acute bronchitis, subacute acute bronchitis of larynx and respiratory syncytial virus infection. Generally, this kind of infectious cough has no obvious regularity of alternating day and night, and it will cough during the day and night. It will also be accompanied by sneezing, runny nose, dry throat, sore throat, burning, headache and general discomfort.

② Cough variant asthma

It is a special type of bronchial asthma. The clinical symptoms are that most people don't cough during the day, but they start coughing after falling asleep at night, or they may start coughing in the morning. When they encounter strong cold air or exercise, coughing will cause it. Generally, dry cough is dominant, and most of them have no phlegm. It also has a feature that antibiotic treatment is useless, and it must be diagnosed and treated by bronchodilators to significantly alleviate cough. If the child's dry cough keeps getting worse or worse at night 1 month, parents need to be careful of cough variant asthma and send it to the doctor immediately.

③ Upper respiratory cough syndrome

It used to be called "postnasal drip syndrome". Refers to a variety of diseases that appear in the upper airway (nose, pharynx and larynx), including various sinusitis, chronic sinusitis, paranasal sinusitis, nasal polyps, tonsil hypertrophy and chronic pharyngitis. Its main feature is that the key to cough occurs when you get up in the morning or when your posture changes (you fall asleep and lie down at night). It may be a dry cough, or you may have phlegm in your throat, and you will spit out light green thick sputum or white foam sputum. At the same time, it is accompanied by discomfort such as stuffy nose, runny nose, foreign body sensation in the throat and pharynx. If the child does not cough with runny nose during the day, but coughs at night, it is caused by nasal drip caused by rhinitis. Because the child has a runny nose when lying down, it is very easy to flow back to the throat and irritate the throat, resulting in cough.

④ Cough after infection

It is mainly caused by various infections, the most common cause is respiratory virus infection, as well as mycoplasma pneumoniae and chlamydia pneumoniae infection. The main feature is that it lasts for a very long time (after the acute symptoms of infection, the cough will continue for 2-8 weeks), but it will improve itself and relieve itself without any treatment. Cough usually occurs during the day and at night, but some children will cough more frequently at night because of their increased sensitivity to cough.

⑤ Gastroesophageal reflux

As the name implies, it is due to the contents of the stomach, such as gastric juice, food, etc., which flow back from the stomach to the throat, causing the trachea to be stimulated and thus causing cough. Its symptom is that the key to cough occurs during the day, which is manifested as a burst of dry cough or wet cough, especially after eating, which may aggravate the cough. In addition to the above five most common causes of cough, it is necessary to pay attention to whether the child has allergic cough and non-infectious acute bronchitis, and pay attention to checking whether there are allergens or environmental pollutants in the bedroom, such as Aspergillus flavus, small pets and dermatophagoides farinae.