Sputum, often known as phlegm, is a coughed-up mixture of saliva and mucus. Bloody sputum can occasionally be associated with some conditions of the respiratory system.
Blood-tinged sputum can be a sign of a significant medical problem. It is a rather common event that isn’t usually a cause for alarm.
Seek medical help right away if you’re coughing up blood with little or no phlegm.