Blood in the sputum or mucus when a person coughs or spits is called hemoptysis. Although the blood can be worrying, it is usually not a cause for concern, especially in young or otherwise healthy people.

Blood in the sputum is a common event in many mild respiratory conditions, including upper respiratory infections, bronchitis, and asthma.

It can be alarming to cough up a significant amount of blood in sputum or to see blood in mucus frequently. In severe cases, this can result from a lung or stomach condition.

In this article, we discuss the causes and treatments of blood in sputum.

Blood in sputum
Blood in the sputum usually comes from the lungs, but it can also come from the stomach or digestive tract.

A range of factors can lead to blood in the sputum. Also, the blood may originate from different parts of the body.

The blood usually comes from the lungs, but less frequently it can come from the stomach or digestive tract. If the blood comes from the digestive tract, the medical term is hematemesis.

  • From the lungs (hemoptysis). If the blood is bright red, frothy, and sometimes mixed with mucus, it probably comes from the lungs and can result from persistent coughing or a lung infection.
  • From the digestive tract (hematemesis). If the blood is dark and comes with traces of food, it probably originated in the stomach or elsewhere in the digestive tract. This may be a sign of a more serious condition.

Possible causes of blood in the sputum include:

  • Bronchitis. Chronic bronchitis is often behind the appearance of blood. The condition involves persistent or recurring inflammation of the airways, along with a cough and the production of sputum.
  • Bronchiectasis. This describes a permanent enlargement of parts of the lungs’ airways. It often occurs with an infection, shortness of breath, and wheezing.
  • A prolonged or severe cough. This can irritate the upper respiratory tract and tear the blood vessels.
  • A severe nosebleed. Many factors can cause nosebleeds.
  • Drug use. Drugs, such as cocaine, that are inhaled through the nostrils can irritate the upper respiratory tract.
  • Anticoagulants. These medications prevent the blood from clotting. Examples include warfarin, rivaroxaban, dabigatran, and apixaban.
  • Chronic obstructive pulmonary disease (COPD). COPD is a permanent obstruction of airflow from the lungs. It usually causes difficulty breathing, a cough, the production of sputum, and wheezing.
  • Pneumonia. This and other lung infections can cause bloody sputum. Pneumonia is characterized by inflammation of the lung tissue, usually because of a bacterial infection. People with pneumonia tend to have chest pain when breathing or coughing, fatigue, fever, sweating, and chills. Older adults can also experience confusion.
  • Pulmonary embolism. This refers to a blood clot in one artery of a lung. It usually causes chest pain and sudden shortness of breath.
  • Pulmonary edema. This describes fluid in the lungs. Pulmonary edema is most common in people with heart conditions. It causes pink and frothy sputum, as well as severe shortness of breath, sometimes with chest pain.
  • Lung cancer. A person is more likely to have lung cancer if they are older than 40 and smoke tobacco. It can cause a cough that does not go away, shortness of breath, chest pain, and sometimes bone pain or headaches.
  • Neck cancer. This usually starts in the throat, larynx, or windpipe. It can cause a swelling or sore that does not heal, a permanent sore throat, and a red or white patch in the mouth.
  • Cystic fibrosis. This inherited condition severely damages the lungs. It usually causes difficulty breathing and a persistent cough with thick mucus.
  • Granulomatosis with polyangiitis. This describes inflammation of the blood vessels in the sinuses, lungs, and kidneys. It usually causes a runny nose, nosebleeds, shortness of breath, wheezing, and a fever.
  • Tuberculosis. A bacteria causes this severe lung infection, which can lead to a fever, sweating, chest pain, pain while breathing or coughing, and a persistent cough.
  • Narrowed heart valves. A narrowing of the heart’s mitral valve, called mitral valve stenosis, can cause shortness of breath, especially with exertion or when lying down. Other symptoms include swollen feet or legs and heart palpitations or fatigue, particularly with increased physical activity.
  • A serious injury. Trauma to the chest can cause blood to appear in the sputum.

Visiting the doctor
A person who is coughing blood in large amounts, or at frequent intervals, should visit a doctor.

See a doctor or seek emergency care when coughing brings up a lot of blood, or any blood at frequent intervals.

If the blood is dark and appears with pieces of food, go to a hospital immediately. This can indicate a severe problem originating in the digestive tract.

Also, see a doctor if any of the following symptoms accompany blood in the sputum:

  • a loss of appetite
  • unexplained weight loss
  • blood in the urine or stools
  • chest pain, dizziness, fever, or light-headedness
  • worsening shortness of breath

To determine whether a medical condition is causing blood to appear in the sputum, a doctor will usually take a medical history and perform a physical examination.

During the examination, the doctor may ask the person to cough, and they may check the nose and mouth for sites of bleeding. The doctor may also take samples of sputum and blood for testing.

In some cases, additional examinations are necessary. These may include a chest X-ray, a CT scan, or a bronchoscopy, which involves a camera at the end of a tube being inserted into the airway.

Steroids may help if an inflammatory condition is causing the bleeding.

Treatments aim to stop the bleeding and treat the underlying cause.

Possible treatments include:

  • Steroids. Steroids can help when an inflammatory condition is behind the bleeding.
  • Antibiotics. Antibiotics are used in cases of pneumonia or tuberculosis.
  • A bronchoscopy. This provides a close look at possible sources of bleeding. An instrument called an endoscope is inserted into the airways through the nose or mouth. Tools can be attached to the end. Some are designed to stop bleeding, while others, for example, can remove a blood clot.
  • Embolization. If a major blood vessel is responsible for blood in the sputum, a doctor may recommend a procedure called embolization. A catheter is passed into the vessel, the source of the bleeding is identified, and a metal coil, chemical, or fragment of gelatin sponge is used to seal it off.
  • Blood product transfusion. A transfusion of elements in the blood, such as plasma, clotting factors, or platelets, may be required if clotting problems or excessively thin blood are responsible for the appearance of blood in sputum.
  • Chemotherapy or radiotherapy. These may be used to treat lung cancer.
  • Surgery. This may be required to remove a damaged or cancerous portion of the lung. Surgery is usually considered a last resort and only an option when bleeding is severe or persistent.

Blood in sputum, particularly in small quantities, is usually not a cause for concern. However, in people with a medical history of respiratory problems or who smoke, it often requires further evaluation.

Respiratory infections, other lung conditions, and less commonly problems in the digestive tract can cause the blood to appear. Some causes are mild and resolve on their own. In other cases, medical intervention is necessary.

If a coughs up blood in large amounts or at frequent intervals, they should see a doctor.

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