Blood in your mouth is often a result of trauma to your mouth or throat, such as chewing or swallowing something sharp. It could also be caused by mouth sores, gum disease, or even vigorous flossing and brushing of your teeth.

If you’re coughing up blood, it might appear that your throat is bleeding. However, it’s far more likely that the blood is originating elsewhere in your respiratory tract or in your digestive tract.

Keep reading to learn why you might find blood in your throat, and when to see a doctor.

Blood in your throat may be caused by infection, anticoagulant medications, certain health conditions, or trauma to the mouth, throat or chest area. Here’s a summary of possible causes:

Injury or trauma to the mouth, throat, or chest could result in blood in your mouth or sputum.

Mouth or throat injury

An injury to your mouth or throat might happen if you bite on something hard, or if you take a hard blow to the mouth or throat area (such as in sports, a car accident, a physical assault, or a fall).

Blood in your mouth could also be caused by mouth sores, mouth ulcers, gum disease, bleeding gums, or aggressive tooth brushing/flossing.

Chest injury

A blow to the chest can cause a bruised lung (pulmonary contusion). One of the symptoms of a severe blow to the chest area can be coughing up blood or blood-stained mucus.

Infections occur when a foreign organism — such as bacteria or viruses — enters your body and causes harm. Some infections can cause you to cough up blood-tinged saliva or mucus, these include:

  • Bronchiectasis. When chronic infection or inflammation causes the walls of your bronchi (airways) thicken and accumulate mucus, you have bronchiectasis. A symptom of bronchiectasis includes coughing up blood or mucus mixed with blood.
  • Bronchitis. Your bronchial tubes carry air to and from your lungs.Bronchitis is an inflammation of the lining of your bronchial tubes. If your bronchitis is chronic (a constant inflammation or irritation), you might develop a cough that produces sputum streaked with blood.
  • Pneumonia. Symptoms of pneumonia, a lung infection, include a cough that produces yellow, green, or bloody sputum, rapid and shallow breathing, fever, chills, shortness of breath, chest pain, fatigue, and nausea.
  • Severe or prolonged cough. When a cough lasts longer than 8 weeks, it’s considered a chronic cough. A chronic cough can irritate the upper respiratory tract and tear the blood vessels resulting in coughing up blood or bloody mucus. A chronic cough could be a symptom of an underlying condition, such as asthma, postnasal drip, or gastroesophageal reflux disease.
  • Tonsillitis. Although tonsillitis, an inflammation of your tonsils, can be a bacterial infection, viruses are the most common cause. In rare instances, tonsillitis can cause bleeding. If your doctor recommends a tonsillectomy (removal of your tonsils), there might be some post-operative bleeding.
  • Tuberculosis. Caused by a bacteria, tuberculosis can cause symptoms such as a severe and persistent cough, coughing up blood or bloody sputum, weakness, chest pain, loss of appetite, chills, and fever.

See a doctor if you’re coughing up blood

Unexplained coughing up of blood should not be taken lightly. Make an appointment with a doctor for a diagnosis and treatment recommendation.

Prescription medications that prevent blood from clotting (called anticoagulants) can have side effects such as coughing up blood.

Other side effects of anticoagulants can be blood in your urine, nosebleeds that do not stop quickly, and vomiting blood. These medications include:

According to the Mayo Clinic, using cocaine can also result in coughing up blood.

Certain conditions are characterized by coughing and, sometimes, blood appearing in the throat or sputum, including:

  • Chronic obstructive pulmonary disease (COPD). COPD is a group of lung diseases including chronic bronchitis and emphysema. Symptoms include shortness of breath, chest tightness, frequent respiratory infections, wheezing, and an ongoing cough that produces a lot of yellowish phlegm.
  • Cystic fibrosis. Cystic fibrosis is an inherited condition that severely impacts the respiratory tract. Symptoms include difficulty breathing, wheezing, frequent chest colds, frequent sinus infections, and a persistent cough with thick mucus.
  • Granulomatosis with polyangiitis. This rare disorder previously called Wegener’s granulomatosis can be fatal without treatment. Symptoms include coughing (sometimes with bloody sputum), pus-like drainage from your nose, sinus infections, nosebleeds, shortness of breath, fatigue, joint pain, and fever.
  • Lung cancer. Common symptoms of lung cancer include a persistent cough, chest pain, coughing up blood or bloody sputum, shortness of breath, fatigue, hoarseness, loss of appetite, and persistent infections.
  • Mitral valve stenosis. Mitral valve stenosis is a narrowing of the heart’s mitral valve. Symptoms include shortness of breath, chest discomfort, fatigue, dizziness, heart palpitations, and coughing up blood.
  • Pulmonary edema. Caused by excess fluid in the lungs, pulmonary edema is a medical emergency typically caused by heart problems. Symptoms include frothy sputum with blood, severe shortness of breath, heart palpitations, and anxiety.
  • Pulmonary embolism. Typically caused by a blood clot, a pulmonary embolism is a blockage in a pulmonary artery in your lungs. Symptoms include chest pain, shortness of breath, and a cough that produces blood or bloody mucus.

If you’re coughing up blood, your doctor must quickly determine where the blood is coming from and why. First, they’ll identify the site of the bleeding and then establish why you’re coughing up blood.

If there’s blood in your mucus or sputum when you cough, the blood is mostly likely coming from your respiratory tract. The medical term for this is hemoptysis. If the blood is coming from your digestive tract, it’s called hematemesis.

Doctors can often determine the location of the bleeding by the color and texture of the blood:

  • Hemoptysis. The blood is typically bright red and frothy. Sometimes it is mixed with mucus.
  • Hematemesis. The blood is usually dark. Sometimes it’s mixed with traces of food.

If you’re coughing up blood, your treatment will depend on the underlying condition causing it, such as:

  • cough suppressants for a prolonged cough
  • surgery to treat a blood clot or tumor
  • antibiotics for infections like bacterial pneumonia or tuberculosis
  • steroids to treat an inflammatory condition behind the bleeding
  • antivirals to reduce the severity or duration of a viral infection
  • chemotherapy or radiotherapy to treat lung cancer

If you’re coughing up large amounts of blood, before addressing the underlying cause, treatment will focus on stopping the bleeding and preventing blood and other material from getting into your lungs (aspiration).

Once these symptoms are stabilized, the underlying cause of the blood being coughed up will be treated.

Unexplained coughing up of blood should not be taken lightly. Make an appointment with a doctor for a diagnosis and treatment recommendation.

It’s especially important to see a doctor if blood in your sputum is accompanied by:

Seek emergency medical attention if:

  • your cough produces more than a teaspoon of blood
  • the blood is dark and appears with pieces of food
  • you also experience chest pain, shortness of breath, dizziness, or lightheadedness (even if you’re only coughing up trace amounts of blood)

If you don’t already have a primary care provider, you can browse doctors in your area through the Healthline FindCare tool.

If you cough up blood, your first thought might be that your throat is bleeding. However, there’s a large possibility that the blood is originating elsewhere in your respiratory or digestive tract.

Occasional, small amounts of blood in your saliva is usually not a cause for great concern. If you have a medical history of respiratory problems, if you smoke, or if the frequency or amount of blood increases, you should see a doctor.