Unexplained dry cough for more than a year, may be cough variant asthma, chronic bronchitis, psychological cough and other diseases caused by the patient should promptly seek medical attention. 1. Cough variant asthma: patients only cough without wheezing, chest tightness, tightness and other symptoms of asthma, mostly in the inhalation of cold air, dust after the aggravation of the use of salbutamol, methylprednisolone and other drugs for treatment. 2. Chronic bronchitis: unexplained dry cough for more than a year may also be caused by chronic bronchitis, the patient will also have wheezing, shortness of breath and other symptoms, such people should strengthen the physical exercise, if necessary, the use of aminophylline and other drugs for treatment. 3. Psychological cough: If the patient’s cough is a mild or severe dry cough during the day, and the symptoms disappear at night or when focusing, then it should be considered to be caused by psychological factors, mostly seen in children. Such people should relax and take appropriate exercise. The above medications should be used in a standardized and rational manner under the guidance of a professional physician and pharmacist. Prolonged dry cough may have other causes, it is recommended that patients consult a regular hospital in a timely manner, with the doctor to improve the examination, standardized treatment.