Hemoptysis or haemoptysis (see American and British spelling differences) is the expectoration (coughing up) of blood or of blood-stained sputum from the bronchi, larynx, trachea, or lungs (e.g. in tuberculosis or other respiratory infections).
It can result from over-anticoagulation from treatment by drugs such as warfarin.
Cardiac causes like congestive heart failure and mitral stenosis should be ruled out.
The origin of blood can be known by observing its color. Bright red, foamy blood comes from the respiratory tract while dark red, coffee-colored blood comes from the gastrointestinal tract.
Extensive injury can cause one to cough up blood.
The first case report of dental floss pick-related injury presenting with massive hemoptysis: A case report.(Case report)
Mar 11, 2008; Authors: Chun-Ta Huang ; Chao-Chi Ho (corresponding author) [1,2]; Yi-Ju Tsai ; Pan-Chyr Yang  Introduction Massive...