Coughing with phlegm in the morning and no cough in the afternoon may be related to lung infection, bronchitis, pharyngitis and other diseases. 1. Lung infections: due to bacterial or viral infections, the secretions in the lungs increase. When sleeping at night, phlegm cannot be discharged in time and tends to gather in the airways. When getting up in the morning, the body position changes, phlegm is easy to stimulate the airways, causing coughing, which leads to sputum expectoration. This cough and phlegm symptoms are relatively relieved in the afternoon. 2. Bronchitis: especially chronic bronchitis patients, often manifested as early morning paroxysmal phlegm. The cause of this symptom is similar to that of lung infections. Patients with bronchitis can also secrete phlegm normally at night, but can not be discharged in time through coughing, so the morning after waking up can be manifested as coughing, coughing up phlegm relatively heavy, relieved in the afternoon. 3. Pharyngitis: coughing, coughing up sputum and feeling of foreign body in the pharynx after waking up in the morning are the typical symptoms. This phenomenon is often associated with the night mucous secretion attached to the posterior wall of the pharynx. Coughing up phlegm in the morning and not coughing in the afternoon may also be caused by other diseases, and it is recommended that the cause be clarified after timely medical examination and treatment according to medical advice.