What can cause you to cough up blood?

Frank Blood?: Per Mayo Clinic, possible reasons for coughing blood include: chronic bronchitis, bronchiectasis, Pulmonary Tuberculosis, Chronic obstructive pulmonary disease, lung cancer, cystic Fibrosis, pneumonia, abscess of lung, emphysema,pulmonary embolism, chest trauma, parasitic infections. See: http://www.mayoclinic.org/symptoms/coughing-up-blood/basics/causes/sym-20050934

Hemoptysis...: Coughing blood, or hemoptysis, is usually caused by bronchitis. However, malignancy must be ruled out so this symptom must always be evaluated by a doctor!

Airway bleeding: Coughing up blood is never a good thing. Some small streaks can come from your upper airway especially if you have upper airway symptoms such as a very painful sore throat or sinuses for instance, but anything more than that deserves a visit to your doc.