Coughing up blood (blood in phlegm)

Blood coughed up from the airways is a symptom that is never left unexplained. Even a single streak in the phlegm needs an answer to the question of where it came from, and heavy bleeding from the mouth while coughing is an emergency. The cause can be entirely harmless: hard coughing tears the small vessels in the lining of the airways, they bleed and they heal on their own. But lung cancer, tuberculosis and a clot in the lung sit behind the same sign, and the appearance of the blood will not tell them apart. Hence a simple rule: coughing up blood is always looked into, and looked into promptly.

What it looks like

We are talking about blood that comes up with a cough from the lower airways. Several features give it away.

• The blood is bright red and often frothy, because it is mixed with air.
• It is mixed into the phlegm: streaks, specks, a pink or rusty colour, sometimes clots.
• It is preceded by a tickle, a bubbling sensation or warmth in the chest, and what you feel is the urge to cough rather than nausea.
• It appears on coughing, often in repeated small amounts through the day.

The amount varies from a few streaks during a cold to coughing blood by the spoonful. Large amounts of pink frothy phlegm together with severe breathlessness is a different picture altogether, typical of fluid on the lungs, and it needs an ambulance.

The volume of blood does not reflect how serious the cause is. A tumour or tuberculosis often produce nothing more than scanty repeated streaks, while heavy bleeding can come from entirely benign bronchiectasis. What matters is not the quantity but the fact of it and whether it keeps happening.

Blood from the mouth does not always come from the lungs

This distinction is the first thing a doctor makes, and it is worth attempting yourself: the three situations are managed in completely different ways.

A nosebleed. When blood runs backwards down the throat rather than out of the nostril, it is swallowed and coughed out, and it seems to come from the lungs. Clues: blood also comes from a nostril, there is soreness at the back of the nose, there was no cough beforehand, and there has been dry air, a cold, nose-picking, a knock to the nose, or blood-thinning medication. For a heavy nosebleed sit down, lean the head forward, pinch the soft part of the nose for ten to fifteen minutes and breathe through the mouth; if it will not stop, get medical help.

Blood from the mouth and throat: bleeding gums, a bitten tongue, the socket after a tooth extraction, bleeding after tonsil surgery. Looking in the mirror helps, as does noticing that the blood is not mixed into phlegm.

Vomiting blood. This is the one most often mistaken for coughing up blood, and it is bleeding from the gullet or stomach, which is the more dangerous of the two. It differs in almost every respect: it is preceded by nausea and retching rather than coughing; the blood is dark and brownish, like coffee grounds, because it has met stomach acid; it may contain food; it does not froth. Black tarry stools often appear over the same days, and the history includes an ulcer, cirrhosis of the liver, or long-term use of anti-inflammatory painkillers or aspirin. Vomiting blood is also a reason to call an ambulance.

When to call an ambulance

Call an ambulance — the single European number 112 works in Spain, Italy, Portugal, Poland and Ukraine — if any of the following applies.

• There is a lot of blood: not streaks but a mouthful, several spoonfuls, a cupful, or blood that keeps coming with every cough and does not stop. Massive bleeding of this kind is dangerous not through blood loss but because blood floods the airways.
• Blood together with breathlessness, chest pain on breathing in, a racing heart, fainting or dizziness on standing: that is how a clot in the lung presents, especially after recent surgery, a plaster cast, a long flight, or with swelling and pain in one calf.
• Lips turning blue, skin going pale or grey and clammy with cold sweat.
• Large amounts of pink frothy phlegm with a fight for breath, particularly at night, in someone with heart disease.
• Blood appearing after a chest injury, a blow, a fall or a road accident.
• Coughing up blood while taking blood-thinning medicines, if it is more than a few streaks.

While help is on the way: sit the person up or lay them on their side rather than on their back, so that blood does not run into the healthy lung; if it is known which lung is affected, they are laid on that side. Do not give anything to suppress the cough — the blood needs to be coughed clear. Do not give food or drink. Keep what has been coughed up, or photograph it: the doctor needs to judge the volume.

What it most often turns out to be

In most people who come in with streaks of blood in the phlegm the cause proves harmless. But that is known after the investigation, not before it.

• A long, hard cough. In bronchitis or after a viral infection the small vessels in the lining tear and streaks appear in the phlegm. It is the commonest finding and it goes as the cough goes.
• A lower airway infection: bronchitis, pneumonia. There is fever, chest pain, purulent phlegm or a rusty colour to it.
• Bronchiectasis — permanently widened airways with a lot of phlegm and repeated infections. Bleeding with it can be regular and at times heavy.
• Nosebleeds and disease of the back of the nose and sinuses, mistaken for bleeding from the lungs.
• Medicines. Anticoagulants and antiplatelet drugs do not cause bleeding from the airways by themselves, but they bring to light what would otherwise pass unnoticed and make any bleeding worse.

In a proportion of people no cause is found even after a full investigation. That is an acceptable outcome, but it is only concluded once the dangerous possibilities have been ruled out, and such a person is usually followed for a while.

The causes that cannot wait

These are what the investigation is for, and every one of them does better the earlier it is found. None can be ruled out by how the blood looks.

• Lung cancer. Coughing up blood is one of its classic first signs, and in a smoker over forty it is suspicious by definition. It is worrying alongside a cough of more than three weeks, weight loss, hoarseness, pain in the chest or shoulder, or repeated pneumonia always in the same place. A tumour can be small enough for an ordinary chest X-ray to miss it, so a clear X-ray does not close the question if the blood returns.
• Tuberculosis. A cough of more than three weeks, night sweats, a low-grade fever, weakness, weight loss. It must be considered after contact with a case, in anyone who has lived or spent long periods in a country where it is common, and in anyone with a weakened immune system. It is curable but infectious, and delay is dangerous both for the patient and for those around them.
• A clot in the lung, or pulmonary embolism. Sudden breathlessness, chest pain on breathing in, blood on coughing, a fast pulse. The risk is higher after surgery, with prolonged immobility, in pregnancy and after childbirth, on combined hormonal contraception, with cancer and after a previous clot.
• Inflammation of the blood vessels of the lungs and kidneys — a rare but especially dangerous group, including granulomatosis with polyangiitis and Goodpasture's syndrome. They are suspected when blood in the phlegm comes together with blood in the urine, swelling, a stubborn crusting bloody nose and weakness that worsens quickly. Here it is a matter of days.
• Fluid on the lungs from heart failure and narrowing of the mitral valve: pink frothy phlegm, breathlessness lying flat, swelling.
• Abnormal blood vessels in the lungs, including the inherited condition that goes with frequent nosebleeds and small red spots on the lips and fingers.

What raises the risk and what to tell the doctor

How urgent the investigation is depends less on how the blood looks than on who the person in front of the doctor is. Gather the following in advance.

• Smoking: whether you smoke now, for how many years and how much, and when you stopped.
• Age and previous lung disease, past tuberculosis, any cancer in the past.
• Every medicine, especially blood thinners and anti-inflammatory painkillers. An anticoagulant is never stopped on your own — that is the doctor's decision, but it must be mentioned straight away.
• Contact with someone who has tuberculosis, travel, where you live and your living conditions.
• Recent surgery, fractures, a plaster cast, long flights, swelling and pain in a calf.
• Accompanying signs: weight, fever, night sweats, breathlessness, chest pain, blood in the urine, a rash.
• The episode itself: when it first happened, how many times, how much blood each time, and whether it was pure blood or mixed with phlegm.

Before the appointment, do not smoke, do not stop prescribed medicines yourself, and do not try to suppress the cough. If the amount is small and you feel well otherwise, you still need to be seen within days rather than "when there is time".

How it is investigated

First the examination: the doctor listens to the chest, looks at the nose, mouth and throat to rule out a local source of the blood, and checks pulse, blood pressure, oxygen level and temperature. Then blood tests including clotting, and a chest X-ray.

An X-ray answers a great deal but not everything, and a normal result does not explain the bleeding. So with repeated episodes, in smokers, and with any warning sign, a computed tomography scan of the chest is done: it shows both a small tumour and bronchiectasis. Phlegm is examined for tuberculosis and, where needed, for tumour cells; where a clot is suspected the lung vessels are scanned. Bronchoscopy — looking inside the airways through a thin flexible instrument — is used when the source has to be seen directly or a piece of tissue taken.

There is no separate "treatment for coughing up blood": what is treated is what was found — an infection, tuberculosis, a clot, a tumour or inflamed vessels. For heavy bleeding, hospitals have ways of stopping it quickly, including blocking off the bleeding vessel through a catheter.

Online consultation

If there is a lot of blood, or it comes with breathlessness and chest pain, a consultation is not what is needed — an ambulance is. Otherwise an online appointment helps you avoid losing time. From your description a doctor can separate blood coughed up from a nosebleed and from vomited blood, judge from your risk factors how urgent it is, and say plainly whether to go in today or book for this week. They will say which tests make sense and in what order, explain the images and results you already have — including why a clear X-ray does not always close the question — and help you take to the face-to-face appointment everything that will genuinely affect the decision.

This material is for information only and does not replace medical advice.