I always cough what reason is white phlegm

Patients always cough with white sputum is considered to be caused by upper respiratory tract diseases, generally including bronchial asthma, acute and chronic bronchitis, pneumonia, tuberculosis and acute and chronic pharyngitis and other diseases. In addition, long-term smoking patients, may also appear cough white sputum phenomenon, need to go to the hospital as soon as possible for examination and diagnosis, in order to treat.