Why Am I Coughing Up Bloody Mucus?

Medically Reviewed on 10/7/2022
Coughing up blood or hemoptysis refers to the spitting of blood
Coughing up blood may be caused by certain benign conditions such as a throat infection or very severe conditions such as lung cancer.

Coughing up blood or hemoptysis refers to the spitting of blood or blood-stained mucus from the throat and lungs (the respiratory tract). Coughed-up blood often looks bubbly and is mixed with mucus. It may be red or rust-colored in appearance. It is often small in amounts, unlike vomiting blood where a large amount of blood is expelled or vomited from the mouth.

Coughing up blood may be caused by certain benign conditions such as a throat infection or very severe conditions such as lung cancer. Due to the possibility of serious underlying conditions, coughing up blood should not be ignored.

Some of the causes of coughing up blood are as follows:

Is a little blood in phlegm normal?

Color of Mucus or Phlegm
What's the Color of Your Mucus or Phlegm?

You may get little streaks of blood in phlegm due to reasons such as excessive coughing. Blood in phlegm, however, may be due to serious conditions such as lung cancer, pulmonary embolism, and heart failure.

You must seek medical care for blood in cough/phlegm if:

  • The coughing up of small amounts of blood lasts more than a week.
  • You are coughing up more than a few teaspoons of blood.
  • There is a presence of blood in the urine or stools.
  • You have shortness of breath.
  • You experience chest pain.
  • You feel light-headed or dizzy.
  • There is a presence of fever.
  • You have rapid or excessive unintended weight loss.


COPD (chronic obstructive pulmonary disease) is the same as adult-onset asthma. See Answer

What causes coughing up blood?

Coughing up blood or hemoptysis can have many underlying causes. Reasons range from mild irritation of the throat to severe lung cancer.

You can cough up blood when there is an issue with the respiratory tract (hemoptysis). Some of the common causes of hemoptysis include:

Other rare causes of hemoptysis include:

  • Congestive heart failure because of mitral stenosis
  • A crack or cocaine use
  • Foreign objects lodged in the airways
  • Inflammatory or autoimmune conditions such as:
    • Lupus
    • Granulomatosis with polyangiitis
    • Microscopic polyangiitis (a condition that can damage the blood vessels)
    • Churg–Strauss syndrome (a disorder marked by blood vessel inflammation)
    • Goodpasture disease (a life-threatening autoimmune disorder that attacks tissues in the lungs and kidneys)
    • Behcet disease (rare disorder leading to blood vessel inflammation throughout the body)
  • Lung abscess
  • Benign lung tumors
  • Parasitic infection of the lung
  • Pulmonary arteriovenous malformations (rare vascular anomalies of the lungs)
  • Pulmonary embolism (blood clot in the lung)
  • An injury like a gunshot wound or car accident
  • Use of anticoagulants (blood thinners)
  • Endometriosis
  • Hughes–Stovin syndrome (consists of deep vein thrombosis)
  • Hereditary hemorrhagic telangiectasia (an inherited disorder that causes abnormal connections between arteries and veins)
  • Sarcoidosis (abnormal collections of inflammatory cells that form lumps known as granulomata)

In some cases, while doctors may not diagnose the exact cause of hemoptysis, the condition may go away within 6 months.

Other conditions that can cause coughing up blood include:

  • Pseudohemoptysis: Refers to a condition where the blood comes from the upper digestive tract. Diagnosis is the only way to differentiate between hemoptysis and pseudohemoptysis.
  • Hematemesis: Refers to vomiting ground coffee-like material mixed with a bit of food.

How can doctors determine why I am coughing up blood?

Coughing up blood may be caused by various conditions that may range from mild to serious. To know the exact cause of coughing up blood, you need to consult a doctor. Your doctor may ask details about coughing up blood such as since when you are having it, how much blood you cough up, and whether you have other complaints such as breathlessness, fever, and chest pain. They may also ask about your history of taking any medications or smoking.

To diagnose the cause of coughing up blood, your doctor may ask the following tests to be done: 

  • Computed tomography (CT) scan of the chest
  • Chest X-ray
  • Magnetic resonance imaging (MRI)
  • Sputum examinations such as microscopy or culture to look for infections
  • Lung scan
  • Lung biopsy
  • Bronchoscopy (a procedure in which a flexible tube is inserted through the nose or mouth to examine the lungs and airways)
  • Blood counts
  • Blood clotting test
  • Pulmonary arteriography/angiography (a procedure to see the blood flow through the lungs)
  • Urinalysis

Should I go to the ER for coughing up blood?

coughing up blood
If you cough more than a few teaspoons of blood or if you’ve been coughing blood for more than a week, then you should go to the ER immediately.

If you notice more than a few teaspoons of blood while coughing or you have been coughing blood for more than a week, you should immediately go to the ER. Also, if you notice these symptoms, you should call the ER right away:

Coughing up blood could be a sign of a serious medical condition. If left untreated, the underlying causes may aggravate and lead to other complications.

What are the different stages of hemoptysis?

Hemoptysis is divided into different types based on the blood amount coughed up over 24 hours.

The three main types of hemoptysis include:

  • Scant or mild hemoptysis: Coughing up less than 20 mL or less than a tablespoon indicates mild hemoptysis.
  • Non–life-threatening or nonmassive hemoptysis: Also known as moderate or submassive hemoptysis, this condition refers to when there is coughing up of blood between 20 and 200 mL (about a cup) of blood.
  • Life-threatening or massive hemoptysis: Refers to a condition where you cough up about 100 mL to over 600 mL, or about a pint of blood.

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Medically Reviewed on 10/7/2022