Coughing up phlegm and blood: what to know

Phlegm is mucus brought up from the lower airways. Blood may look bright red, pink, or brown once mixed with mucus. Recent coughing, a sore throat, a nosebleed draining backwards, or inflammation in the breathing tubes can all add blood to what you see. Conditions such as Acute Bronchitis, Bronchiectasis, Asthma, or Chronic Cough may present with phlegm and blood; this does not mean that a symptom by itself identifies one of these conditions.

Tell the clinician whether the blood was streaked through mucus or came up separately, whether it has happened more than once, and whether you also have fever, chest pain, breathlessness, wheezing, or unexplained tiredness.

Arrange a prompt clinical assessment if this is new or unexplained. Note the colour and approximate amount, save a photograph if practical, and list medicines that affect bleeding. Drink fluids if you can do so comfortably, avoid smoking and vaping, and do not take leftover antibiotics or cough medicines prescribed for someone else. A clinician may examine your nose, throat, and chest and decide whether further tests are needed.

Seek emergency help immediately if you are coughing up more than streaks, the bleeding is continuing, or you have trouble breathing, chest pain, faintness, confusion, blue or grey lips, or a fast worsening illness. Get same-day medical advice for repeated blood-stained phlegm, a high fever with feeling very unwell, or blood after a recent procedure or injury.

Ask: Could the blood be from my nose, throat, or lungs? What examination or test is appropriate? Should I change any medicine that affects clotting? What signs should make me return urgently?