A dry cough after getting well from a cold should be considered to be caused by bronchitis, allergic pharyngitis or mycoplasma infection. At this time, you can go to the hospital to further improve the chest X-ray, blood routine and antibodies to Mycoplasma pneumoniae for a clear diagnosis. If the dry cough is accompanied by itchy throat and patients who usually have rhinitis are mostly considered to be caused by allergic pharyngitis, oral loratadine, ketotifen, cetirizine, etc. can be taken to reduce airway hyperreactivity and inflammation. If the patient is positive for Mycoplasma pneumoniae antibodies, the patient is considered to have Mycoplasma pneumoniae bronchitis and can be treated with oral azithromycin. If the patient has a long cough and it is accompanied by low fever, chest pain, hoarseness or afternoon hot flashes and night sweats, it is recommended to improve chest CT examination to exclude tuberculosis and lung cancer.