Coughing is a reflex action of the body to protect itself and is not a separate disease. After a cough appears, it is necessary to see a doctor promptly in the following cases: 1. Small infants under three months old have just been born, their entire immune system is not yet perfect, their own immune system functions are lower, and their ability to compensate is poor, plus the condition changes quickly, and when the symptoms are heavy, the condition may already be more serious, so children of this age should see a doctor early; 2. Infants with less severe cough symptoms but in poor general condition, such as not eating milk, crying, being irritable, not sleeping well, and having a particularly bad spirit, this situation also requires special attention and there is no need to wait until the cough is heavier before seeing a doctor; 3. Cough is really heavy, with difficulty in breathing, labored breathing, and a poorer complexion, like when an asthma patient has an acute attack with obvious inspiratory difficulty movements; 4. Cough with fever, and a part of it in children is uncommon, or when there is a cough with blood, you need to see a doctor promptly.