Coughing up dark sputum the next morning after taking medicine for a cold may be related to factors such as bleeding caused by severe coughing, long-term smoking and environmental irritation. 1. First of all, consider the intense coughing caused by pulmonary hemorrhage, mainly in the trachea and bronchial mucosal damage, resulting in local bleeding, but can not be coughed up in a timely manner, can be discharged along with the sputum the next morning, dark sputum lumps performance. 2. Long-term smoking, this kind of people due to the influence of tobacco, can cause the trachea and bronchial surface attached to a large number of black substances, coughing up sputum along with the discharge, manifested as black sputum. 3. Environmental stimuli, such as long-term work in coal mines, etc., the bronchial tubes can be attached to coal dust and other substances, can also appear such symptoms. Therefore, it is recommended to consult a doctor in a timely manner, under the guidance of the doctor to carry out relevant examinations, and follow the doctor’s instructions for treatment.