A persistent cough can be a sign of a more serious illness, which is why it's important to get it checked by a doctor.

Today, Dr Zoe helps a reader who has been coughing up blood. Q: I had a health scare in June where I coughed up a blood clot. I had a fast-track cancer appointment and was investigated.

My GP said to let him know if it happens again with no explanation of why. A: Coughing up blood from the lungs is called haemoptysis and it’s a symptom that can have several causes. Lung cancer ...