When Is Coughing Up Blood an Emergency?

sick woman coughing

Coughing up blood, otherwise known as hemoptysis, can be very frightening. It can also be confusing at first. Is the blood truly coming from your lungs or could it be from a nosebleed, your esophagus, or from your stomach?


Hemoptysis may occur when there is bleeding in the throat, the trachea, or in the large or small airways of the lungs (the bronchi or the bronchioles). Many people describe their symptom as spitting up blood-streaked mucus.

Blood that is coughed up is often mixed with phlegm and can have a bubbly appearance.

It is important to make a distinction between coughing up blood and blood that is brought up through your mouth from other regions of your body. “Pseudohemoptysis” is a term that describes spitting up blood that doesn’t come from your lungs or bronchial tubes. "Hematemesis" is a term that refers to blood that comes from your esophagus and stomach (throwing up blood.)


If you cough up blood it doesn’t necessarily mean you have lung cancer. There are many conditions that can cause this symptom—and only one of these is lung cancer. Hemoptysis is the only symptom in only seven percent of people diagnosed with lung cancer. But since the outlook for lung cancer is better the earlier it's diagnosed, it is important to consult your doctor as soon as possible.

The most common causes of coughing up blood are irritation in the airways from coughing or an infection.

Some possible causes of blood streaked sputum include:

  • Inflammation and irritation of the airways from repeated coughing
  • Bronchitis
  • Bronchiectasis
  • Lung cancer
  • Pneumonia
  • Pulmonary edema
  • Blood clots in the lungs (pulmonary embolus)—With pulmonary emboli, people often have pain, redness, or swelling in their calves due to deep vein thrombosis.
  • Tuberculosis—This is the most common cause of coughing up blood worldwide, but less common in the United States.
  • Inhalation of a foreign body
  • Bleeding disorders—These can be inherited or due to medications or supplements that increase the time it takes for your blood to clot.

When to Seek Medical Attention

Coughing up blood can quickly become an emergency. Coughing up more than one teaspoon of blood is considered a medical emergency. Coughing up 100cc of blood—only 1/3 of a cup—is called massive hemoptysis and has a mortality (death) rate of 30 percent. Don't try to drive yourself or have someone else drive you to the hospital—call 911.

You should also call 911 immediately if you experience chest pain, shortness of breath, or lightheadedness, even if you cough up just a trace of blood. The problem is that coughing up blood can quickly cause airway obstruction and aspiration of the blood into your lungs.


If you cough up blood—even a very slight amount just once—it is important to make an appointment to see your physician. If possible, bring a sample of what you have been coughing up to your doctor’s appointment. Wrapping the sample in plastic wrap or wax paper can preserve the sample better than wrapping it in tissue.

You doctor will ask you several questions in addition to performing a careful physical exam. Some of these include:

  • How long has this been happening?
  • When did it begin?
  • Did it occur while you were eating?
  • How much blood did you cough up?
  • Was the blood mixed with mucus?
  • What other symptoms have you been experiencing? For example, a persistent cough, allergy symptoms, shortness of breath, hoarseness, wheezing, unexplained weight loss, or fatigue.
  • Have you had any episodes of choking?
  • Do you, or have you ever, smoked?
  • What medications are you taking (including any herbal supplements or over-the-counter medications)?
  • What other medical conditions do you have?
  • Has anyone in your family had bronchitis, bleeding disorders, lung problems, or lung cancer?

Depending upon the amount of blood you are coughing up, your doctor will first want to make sure your airway is okay to prevent aspiration (breathing in the contents that are present in your mouth) and control any active bleeding. He/she will then recommend tests to determine the cause. Possible tests may include:

  • Lab tests to check your blood counts and look for any reason for bleeding
  • A chest x-ray to look for infection of any evidence of a tumor
  • A CT scan of your chest
  • bronchoscopy to check for foreign bodies or evaluate your airways for a tumor

It's important to be your own advocate and to keep asking questions if an answer is not found. Lung cancers are often missed on regular chest x-rays and further testing is needed. If you aren't getting answers, consider getting a second opinion.


Treatment will depend on the cause of your symptoms as well as the amount of blood you have been coughing up. Remember that if you only cough up blood once, and even if it is a small amount, it is still extremely important to see your doctor as soon as possible.

If you are actively bleeding, a CT scan is usually the imaging test of choice to evaluate bleeding. Most bleeding in the airways stems from the bronchial arteries, and bronchial artery embolization (essentially putting a clot in the artery) is often an effective treatment.

Learn about how lung cancer is diagnosed, what you may expect, and your possible risk factors for lung cancer (it goes far beyond smoking and at least one in five women who develop lung cancer have not smoked a single cigarette).

Don't dismiss the chance that you could have lung cancer until the diagnosis has been ruled out. Lung cancer occurs in never-smokers. It occurs in young adults. And it is almost as common in women as in men. Unfortunately, the average time between the onset of symptoms and diagnosis of lung cancer is 12 months—a time during which treatment can often make a difference in the outcome of the disease.

In Children

Coughing up blood in children tends to have different causes than the same symptom in adults. The most common causes are infections, such as pneumonia, bronchitis, and tuberculosis.

Roughly a third of the time a cause cannot be determined and the symptom goes away without finding a cause. Around six percent of children with hemoptysis have been found to have underlying heart disease and, in around four percent, a cancer has been found to be the cause.


Bannister, M., and K. Ah-See. Evidence-Based Management of Haemoptysis by Otolaryngologists. Journal of Laryngology and Otology. 2015. 129(8):807-11.

Simon, D., Aronoff, S., and M. Del Vecchio. Etiologies of Hemoptysis in Children: A Systematic Review of 171 Patients. Pediatric Pulmonology. 2017. 52(2):255-259.

Yendamuri, S. Massive Airway Hemorrhage. Thoracic Surgery Clinics. 2015. 25(3):255-60.