What should you know about coughing up bright blood?

Coughing up bright blood can signal bleeding in the airways or lungs and needs prompt medical assessment, especially when it continues or affects breathing. The medical term is haemoptysis. Blood may appear as streaks in phlegm, small clots, or fresh red fluid. Even a small amount can be difficult to judge at home, so note what you saw and arrange advice promptly. Severe or repeated bleeding is an emergency.

Bright blood after coughing may come from an irritated throat or airway, particularly after forceful coughing, but it can also arise deeper in the respiratory system. Chest infections such as pneumonia can cause blood-stained phlegm. Bronchiectasis, tuberculosis, lung cancer, and a pulmonary embolism are other possible causes that clinicians may need to consider. These conditions differ in urgency and treatment; the symptom alone cannot identify the cause.

Blood from the lungs is usually mixed with mucus and appears during or immediately after coughing. Blood from the nose or mouth can run backwards and then be spat out, while blood from the stomach is more often brought up with nausea or vomiting and may look dark or altered. Tell the clinician exactly how it appeared, along with any fever, breathlessness, chest discomfort, weight change, night sweats, or recent infection.

Stop strenuous activity and sit upright. Keep any tissue or container showing the blood if it helps describe the amount and appearance. Do not smoke, and avoid taking additional doses of medicines that can increase bleeding unless a clinician has told you to take them. Do not drive yourself if you feel faint, short of breath, or unwell.

Seek same-day medical advice even if the bleeding settles, because the cause may need an examination and tests. Have your medication list ready, including blood thinners, and mention recent travel, surgery, long periods of immobility, tuberculosis exposure, or a history of lung disease. Do not delay care while trying to measure the blood precisely.

Call emergency services now if you are coughing up more than a trace, the bleeding is ongoing or increasing, or you have trouble breathing, chest pain, a fast heartbeat, faintness, confusion, blue lips, or marked weakness. These features can indicate significant airway bleeding or a serious problem affecting the lungs.

Urgent assessment is also needed when coughing up blood follows a chest injury, occurs during pregnancy or soon after giving birth, or happens with one-sided leg swelling and pain. Bring the medication packets or a list of medicines if it is safe to do so.

You can ask: Where is the blood most likely coming from? Which examination or scan is needed? Could my medicines be contributing to bleeding? What warning signs mean I should return immediately? What should I do if the coughing or blood returns?