DefinitionCoughing up blood is the spitting up of blood or bloody mucus from the lungs and throat (respiratory tract).Hemoptysis is the medical term for coughing up blood from the respiratory tract.Alternative NamesHemoptysis; Spitting up blood; Bloody sputumConsiderationsCoughing up blood is not the same as bleeding from the mouth, throat, or gastrointestinal tract.Blood that comes up with a cough often looks bubbly because it is mixed with air and mucus. It is usually bright red, although it may be rust-colored. Sometimes the mucus may only contain streaks of blood.Common CausesA number of conditions, diseases, and medical tests may make you cough up blood.Diseases and conditions may include:Blood clot in the lungBronchiectasisBronchitisCancerCystic fibrosisGoodpasture syndromeInflammati