Causes of bloody cough

Small streaks of blood may follow forceful coughing, a dry throat, or inflammation in the breathing tubes. Blood can also occur with Acute Bronchitis or a Common Cold, especially when mucus is thick and the airways are irritated. Allergic Rhinitis or Acid Reflux can trigger repeated coughing that leaves the throat sore. Asthma, Bronchiectasis, and a Chronic Cough may also cause recurring airway irritation. The colour, amount, frequency, and whether the blood is mixed with mucus help a clinician judge the cause. Blood from the nose or gums can sometimes be mistaken for blood from the lungs.

Arrange medical advice for any unexplained blood with coughing, even if it appears as a small streak. Note when it started, how often it occurs, the amount, its colour, and any fever, chest pain, wheeze, breathlessness, night sweats, or weight change. Do not smoke, and avoid medicines that affect bleeding unless a clinician has advised you how to take them. A clinician may listen to your chest and decide whether tests are needed.

Seek emergency care if you are bringing up more than a small streak, have trouble breathing, severe chest pain, faintness, confusion, blue lips, or bleeding that does not stop. Urgent assessment is also needed if the cough follows a chest injury or occurs with a very fast heartbeat. Do not drive yourself if you feel faint or severely breathless.

Could the blood be coming from my nose or throat? What signs would make this an emergency? Do my medicines, smoking history, or repeated chest infections change the assessment?