It is important to find out how long you have been coughing for. Clinically, coughs are classified by time and can be divided into acute cough, subacute cough and chronic cough. Acute cough is a cough that lasts less than 2 weeks, subacute cough is a cough that lasts 2-4 weeks, and chronic cough is a cough that lasts more than 4 weeks. Acute coughs and some subacute coughs are usually caused by colds, bronchitis, pneumonia, and allergic coughs due to allergies. The chronic cough that is greater than 4 weeks is mostly cough variant asthma, or asthma. The doctor will need to do an auscultation examination to understand the condition of the lungs; he or she will also need to take x-rays to see if there is any infection of bronchitis or pneumonia; furthermore, children who can cooperate with inhalation and blowing will need to do pulmonary function tests. Once the diagnosis is clear, you need to cooperate with the doctor to do the corresponding treatment, such as: common cold, you can take oral cough medicine; bronchitis, pneumonia, depending on the nature of the infection, you can take oral antibiotics, together with cough medicine; allergic cough or cough variant asthma, asthma, mainly hormone inhalation treatment, together with oral anti-allergy drugs and other combined treatment. Along with treatment, attention needs to be paid to a light diet, avoiding strenuous exercise, and children with allergies also need to avoid allergens as much as possible.