Coughing up blood: what to do

Coughing up blood, called haemoptysis, means blood has entered mucus from the airways or lungs. It may follow an irritated throat or forceful cough, but it can also accompany pneumonia, bronchiectasis, tuberculosis, a clot in the lung, or lung cancer. Blood from the nose, mouth, or stomach can look similar, so describe whether it appeared with a cough, tasted acidic, or followed vomiting. The pattern and associated symptoms help a clinician decide how quickly to investigate.

Sit upright and avoid exercise while arranging care. Spit blood into a tissue or container rather than swallowing it, if possible, and note its colour, amount, timing, and whether it was mixed with mucus. Keep a list of medicines, especially those affecting clotting. Avoid smoking. Do not stop prescribed treatment or start an over-the-counter cough medicine without advice, because the right choice depends on the cause and the amount of bleeding.

Call emergency services if bleeding is heavy or repeated, breathing becomes difficult, chest pain develops, you feel faint or confused, your lips look blue, or your heartbeat is unusually fast. Emergency assessment is also needed after a significant injury or when a blood-thinning medicine is involved. If the episode was only a small streak and has stopped, still arrange prompt medical advice rather than assuming it was minor.

Tell the clinician when it started, how often it occurred, and whether fever, breathlessness, chest pain, night sweats, or weight change are present. Ask whether you need a chest examination, imaging, sputum testing, or a medication review, and ask what to do if the bleeding returns.