If you often smoke or are in a bad environment with more dust and dirt, and inhale more during sleep, it will lead to black sputum in the morning, when you must quit smoking, and at the same time maintain the hygiene of your personal environment and do a good job of protection. Pharyngitis or rhinitis causes bleeding in the mouth and bleeding from the nasal mucosa to flow to the throat, resulting in blood within the sputum, so it will show black sputum, which can be treated with ribavirin, cephalosporins to eliminate inflammation or throat-clearing and throat-suppressing drugs. If the lungs and respiratory tract are infected with inflammation, such as bronchitis, pneumonia, tuberculosis, or lung tumors, the symptoms of black sputum will also appear.