Blood during cough: what to know

Airway infections such as acute bronchitis and a common cold can inflame the lining and lead to streaks of blood. Ongoing cough, asthma, bronchiectasis, acid reflux, or nasal drainage can also keep tissues irritated. A clinician may ask about smoking, medicines that affect clotting, fever, chest pain, breathlessness, and how much blood you saw. The symptom alone does not identify its cause.

Note the colour, amount, timing, and whether blood was mixed with mucus. Avoid smoking and strenuous activity until you have advice, and do not start or stop prescription medicines without speaking with a clinician. Arrange prompt medical review for a first episode, repeated episodes, or blood that continues. Bring a list of medicines and describe any recent infection.

Seek emergency help if bleeding is more than a few streaks, keeps coming, or makes breathing difficult. Urgent assessment is also needed with chest pain, faintness, confusion, blue lips, severe weakness, or a fast worsening illness. These signs can indicate significant bleeding or a serious problem affecting the lungs or circulation.

Ask which tests may distinguish an irritated airway from infection or another cause, whether your medicines could contribute, and what changes should prompt emergency care. Ask how to record further episodes and when follow-up is needed.