Old cough is a relatively common clinical symptom of respiratory disease and can be triggered by a variety of diseases, such as bronchitis, pneumonia, wind fever, pharyngitis, etc. Coughing is a protective reflex response of the body that removes secretions from the respiratory tract and also removes abnormal substances that enter the respiratory tract. A prolonged and frequent cough is a pathological cough. The main causes of coughing are: respiratory diseases caused by viral and bacterial infections, such as inflammation of the throat, trachea, lungs, bronchi, etc., which may cause coughing; inhalation of irritating gases and foreign bodies such as cold air, hot air, acidic substances, dust, etc., and the presence of tumors in the body, etc.; pleural diseases, such as pleurisy and irritation of the pleura, which can also cause coughing; and cardiovascular diseases, such as pulmonary edema, which can also cause coughing. Cardiovascular diseases can also trigger coughing, such as pulmonary edema and bronchoalveolar exudate, and central nervous system diseases can also trigger coughing, such as meningitis and encephalitis. In short, coughing all the time can be caused by different diseases. It needs to be clearly diagnosed according to different causes so that targeted treatment can be carried out, mainly anti-inflammatory, anti-allergic, coughing and phlegm relief. In life, patients should pay attention to their diet, do not eat spicy and stimulating food, pay attention to eating more fresh vegetables and fruits, and drink water boiled with pears. This is beneficial to the control of the disease.