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Coughing Up Blood


Rebecca Dezube

, MD, MHS, Johns Hopkins University

Reviewed/Revised Nov 2023
Topic Resources

Coughing up blood from the respiratory tract is called hemoptysis. The amount of blood produced can vary from a few streaks of blood mixed with normal sputum to large amounts of pure blood. Other symptoms, such as fever and difficulty breathing, may be present, depending on the cause of hemoptysis.

Causes of Coughing Up Blood

Although hemoptysis can be frightening, most causes turn out not to be serious. Blood-streaked sputum is common in many minor respiratory illnesses, such as upper respiratory infections (URIs) and viral bronchitis. Sometimes the cause is blood from the nose that has traveled down the throat and then is coughed up. Such blood is not considered hemoptysis.

Common causes

Less common causes

Other causes include a blood clot in an artery in a lung (pulmonary embolism Pulmonary Embolism (PE) Pulmonary embolism is the blocking of an artery of the lung (pulmonary artery) by a collection of solid material brought through the bloodstream (embolus)—usually a blood clot (thrombus) or... read more ) and, less commonly, inflammation of blood vessels (vasculitis Overview of Vasculitis Vasculitic disorders are caused by inflammation of the blood vessels (vasculitis). Vasculitis can be triggered by certain infections or drugs or can occur for unknown reasons. People may have... read more Overview of Vasculitis ) in the lung, such as Goodpasture syndrome Goodpasture Syndrome Goodpasture syndrome is an uncommon autoimmune disorder in which bleeding into the lungs and progressive kidney failure occur. People usually have difficulty breathing and may cough up blood... read more or granulomatosis with polyangiitis Granulomatosis with Polyangiitis Granulomatosis with polyangiitis often begins with inflammation of small- and medium-sized blood vessels and tissues in the nose, sinuses, throat, lungs, or kidneys. The cause is unknown. The... read more Granulomatosis with Polyangiitis . Heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more Heart Failure (HF) and heart valve disorders Overview of Heart Valve Disorders Heart valves regulate the flow of blood through the heart's four chambers—two small, round upper chambers (atria) and two larger, cone-shaped lower chambers (ventricles). Each ventricle has... read more Overview of Heart Valve Disorders can rarely cause mild hemoptysis.

Massive hemoptysis

Risk factors

Some conditions increase the risk that hemoptysis is caused by a serious disorder:

Evaluation of Coughing Up Blood

The following information can help people decide whether a doctor's evaluation is needed and help them know what to expect during the evaluation.

Warning signs

In people with hemoptysis, the following symptoms are of particular concern:

  • Large amounts of blood coughed up

  • Shortness of breath

  • Signs of significant blood loss (weakness, dizziness when standing up, thirst, sweating, and a rapid heart rate)

  • Weakness or fatigue

  • Having a tracheostomy

When to see a doctor

People with warning signs should go the hospital immediately. People without warning signs who have risk factors for serious disorders and those with more than just blood-streaked sputum should see a doctor in a day or two.

If people have only blood-streaked sputum (which is usually caused by an upper respiratory infection), a doctor's evaluation is not as urgent. People can call a doctor, who can decide whether and how rapidly they need to be seen based on their symptoms, medical history, and other factors. Typically, a delay of a few days or so is not harmful.

What the doctor does

Doctors first ask questions about the person's symptoms and medical history and then do a physical examination. What doctors find during the history and physical examination often suggests a cause and the tests that may need to be done (see table ).

Doctors ask

  • When the person started coughing up blood

  • How long the coughing has been going on

  • Whether anything specific triggers it (such as cold, exertion, or lying down)

  • About how much blood is coughed up (such as streaks, a teaspoonful, or a cupful)

  • Whether the person has other symptoms, such as fever, weight loss, chest pain, or leg pain

Doctors determine whether blood was actually coughed (and not vomited or dripped down the back of the throat from a nosebleed).

Doctors ask people about their medical history (if not already known) and their risk factors for causes. A history of frequent nosebleeds, easy bruising, or liver disease suggests a possible blood clotting disorder Overview of Blood Clotting Disorders Blood clots help stop bleeding. Blood clotting (coagulation) disorders are dysfunctions in the body's ability to control the formation of blood clots. These dysfunctions may result in Too little... read more . Doctors review the medications the person is taking to check for those that inhibit clotting (anticoagulants).

During the physical examination, doctors review vital signs to check for fever, rapid heart or breathing rate, and test for a low oxygen level in the blood. They do a full heart and lung examination, inspect the neck veins for signs of fullness such as bulging, and check the legs for puffiness (edema Swelling Swelling is due to excess fluid in the tissues. The fluid is predominantly water. Swelling may be widespread or confined to a single limb or part of a limb. Swelling is often in the feet and... read more Swelling ). Puffiness in one leg may indicate a blood clot (deep vein thrombosis Deep Vein Thrombosis (DVT) Deep vein thrombosis is the formation of blood clots (thrombi) in the deep veins, usually in the legs. Blood clots may form in veins if the vein is injured, a disorder causes the blood to clot... read more Deep Vein Thrombosis (DVT) ). Puffiness in both legs may indicate heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more Heart Failure (HF) . Doctors also examine the abdomen, skin, and mucous membranes. The person is asked to cough during the examination. If any blood is coughed up, the doctor notes its color and the amount of blood. Doctors also check the nose and mouth for bleeding sites.

Clues from the history and examination help doctors determine the cause. A sensation of postnasal drip or any bleeding from the nose, particularly without coughing, may mean that the blood being coughed up has dripped down the back of the throat from the nose. Nausea and vomiting of black, brown, or coffee-ground–colored material usually means that the blood is from the stomach or intestine and is being vomited and not coughed. Frothy sputum, bright red blood, and, if the amount is massive, a sensation of choking usually mean that the blood is from the trachea or lungs (called true hemoptysis).

If cough has just begun and if the person is otherwise in good health and has no risk factors for tuberculosis, fungal infection, or pulmonary embolism, the cause is usually an acute respiratory infection, such as acute bronchitis Acute Bronchitis Acute bronchitis is inflammation of the windpipe (trachea) and the airways that branch off the trachea (bronchi) caused by infection. Acute bronchitis is usually caused by a viral upper respiratory... read more . If coughing up blood is caused by a heart or lung disorder, the person has almost always already been diagnosed with that heart or lung disorder. That is, coughing up blood is usually not the first symptom of a heart or lung disorder.



If hemoptysis is severe, persistent, or unexplained, testing is needed. If people have coughed up massive amounts of blood, they are treated and their condition is stabilized before testing is done.

A chest x-ray Chest Imaging Chest imaging studies include X-rays Computed tomography (CT) CT angiography Magnetic resonance imaging (MRI) read more is taken typically. If the chest x-ray is abnormal or if the person has symptoms of or risk factors for a particular disorder, computed tomography (CT) and bronchoscopy are done. In bronchoscopy, a flexible viewing tube is inserted into the windpipe and bronchi to identify the bleeding site. Occasionally, bronchoscopy is necessary to confirm that blood is being coughed up from the lower airways and not from the nose, stomach, or intestine.

Doctors often check for lung cancer Lung Cancer Lung cancer is the leading cause of cancer death in both men and women. About 85% of cases are related to cigarette smoking. One common symptom is a persistent cough or a change in the character... read more Lung Cancer , especially in people older than age 40 years who smoke (and even in younger people who smoke if they started smoking during adolescence), even if the sputum is only blood-streaked.

In many people, a complete blood count and blood tests that assess the blood's ability to clot are done to detect blood clotting problems.

Despite testing, the cause of hemoptysis is not identified in 30 to 40% of people. However, when hemoptysis is severe, the cause is usually identified.

Treatment of Coughing Up Blood

Bleeding may produce clots that block the airways and lead to further breathing problems. Therefore, coughing is important to keep the airways clear and should not be suppressed with cough suppressants (antitussive medications).

Hemoptysis may be mild and may stop by itself or when the disorder causing the bleeding (such as heart failure or infection) is successfully treated.

If a large clot blocks a major airway, doctors may have to remove the clot using bronchoscopy.

Rarely, hemoptysis is severe or does not stop by itself. If so, a tube may need to be inserted through the mouth or nose into the windpipe or lower into the airways to help keep the airways open.

If the source of bleeding is a major blood vessel, a doctor may try to close off the bleeding vessel using a procedure called bronchial artery angiography and embolization. Using x-rays for guidance, the doctor passes a catheter into the vessel and then injects a chemical, fragments of a gelatin sponge, or a wire coil to block the blood vessel and thereby stop the bleeding. Sometimes bronchoscopy or surgery may be needed to stop severe or continuing bleeding, or surgery may be needed to remove a diseased or cancerous portion of the lung. These high-risk procedures are used only as last resorts.

If clotting abnormalities are contributing to the bleeding, a person may need a transfusion of plasma, clotting factors, or platelets.

Tranexamic acid, a medication that can be inhaled, may be given to treat hemoptysis that does not resolve on its own or with treatment of the underlying disorder.

Key Points

  • Blood-streaked sputum is usually caused by a respiratory infection and, if it resolves, is not usually cause for worry.

  • A lower respiratory tract infection and inhalation of a foreign object are the most common causes in children.

  • Doctors must distinguish hemoptysis from bleeding that comes from the mouth, nose, or throat and from blood that is vomited.

  • Blood-streaked sputum in people who smoke usually requires further evaluation.

  • People who cough up massive amounts of blood must be treated and stabilized immediately, before testing can be done.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Cyklokapron, Lysteda
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