Coughing up blood (blood in phlegm)
Causes of coughing up blood
Common causes of coughing up blood include:
- a long-lasting or severe cough
- a lung or airway infection like a chest infection, pneumonia, tuberculosis or bronchitis
- a problem with your airways that causes them to widen and produce more mucus (bronchiectasis)
Sometimes coughing up blood can be a sign of something more serious like a blood clot or lung cancer.
It's important to get it checked out as soon as possible.
Urgent advice: Ask for an urgent GP appointment or get help from NHS 111 if:
- you've coughed up a few small spots, flecks or streaks of blood, or noticed blood in your phlegm or handkerchief
You can call 111 or get help from 111 online.
Immediate action required: Call 999 or go to A&E immediately if:
- you're coughing up more than just a few spots or streaks of blood
- you're coughing up blood and finding it hard to breathe, have a very fast heartbeat or have pain in your chest or upper back
These symptoms could be a sign of a more serious problem like a blood clot in the lungs (pulmonary embolism).
Page last reviewed: 13 June 2024
Next review due: 13 June 2027