Blood in Saliva | Causes of Bloody Spit, Saliva

The presence of blood in the saliva may not necessarily be an indication of bleeding from the mouth cavity (stomatorrhagia). The mouth communicates with the nose, esophagus and larynx via the throat. This could mean that any bloody saliva may be due to bleeding in the nasal cavity, respiratory or gastrointestinal tracts.

Tracing the cause may be easier if the blood in the saliva is only evident or more pronounced in one of these situations :

  • After or during vomiting, regurgitating or when belching indicates bleeding from the esophagus. Read more under Blood In Vomit.
  • After or during coughing (hemoptysis) or sneezing indicates bleeding from the airways or lungs. Read more under Coughing Up Blood.
  • After sneezing, blowing the nose,  in post nasal drip, with nasal congestion or accompanying a bleed from the nose indicates bleeding from the nasal cavity. Read more under Epistaxis.

If there is blood in the saliva without any clear correlation with the features mentioned above, then pathology within the mouth has to first be excluded before the neighboring cavities are investigated.

In order to help with a diagnosis, it is important to identify if the bleeding is only evident in the saliva during or after one or more of the following :

  • Eating or drinking
  • Biting, chewing or swallowing
  • Brushing, gargling with a mouth rinse or flossing
  • Talking or shouting
  • Breathing through the mouth

Causes of Bloody Saliva

Persistent or recurring mouth sores and ulcers known as recurrent aphthous stomatitis are a common condition and needs to be excluded as a possible site of bleeding. These sores/ulcers may be due to one or more of the causes mentioned below or occur for no known reason (idiopathic).


Vigorous brushing and excessive flossing are the most common causes of blood in the saliva.  Other causes of trauma may include :

  • After dental work/surgery or oropharyngeal surgery
  • Poorly fitting dentures and other dental prosthetics
  • Mouth biting
  • Chemical injury to he mouth may be seen with :
    • Ingesting caustic substances
    • Excessive gum chewing
    • Tobacco chewing
    • Acidic foods


A number of bacteria, even naturally occurring bacteria, may become pathological if there are untreated wounds or sores in the mouth.

Many viral and fungal infections, especially recurrent cases, are seen in immunocompromised patients (HIV, uncontrolled diabetes).

  • Viral
  • Varicella zoster virus (chickenpox)
  • Herpes simplex virus (HSV-1)
  • Epstein-Barr virus (EBV)
  • Cytomegalovirus (CMV)

Bleeding from the mouth is seen with many uncommon tropical infections and hemorrhagic fevers.

  • Fungal
  • Candida spp (candidiasis)
  • Mucorales spp (mucormycosis)

Nutritional Deficiencies

Pathology in the mouth due to nutritional deficiencies may result in lesions that could lead to bleeding in the mouth.

  • Scurvy – vitamin C
  • Pellagra – vitamin B3/niacin
  • Iron-deficiency anemia – iron

Drugs and Toxins

Stomatorrhagia (bleeding in the mouth) is commonly seen in patients undergoing chemotherapy and/or radiation therapy. Radiation sickness may also cause mouth bleeding. Warfarin and other anticoagulants may lead to profuse bleeding due to even minor trauma in the mouth.

Other substances :

  • Poisons, including venom
  • Narcotics like crystal meth (long term ~ meth mouth)


  • Oral cavity cancer (primary)
  • Lymphoma
  • Leukemia

Blood and Bleeding Disorders

  • Thrombotic thrombocytopenic purpura
  • Thrombocytopenia
  • Hemophilia
  • Von Willebrand’s disease

Articles Related to Bloody Saliva

  1. Blood in Mouth
  2. Sore Mouth
  3. Bleeding Gums

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  • mesia

    Hi, I have had a deep cough associated with earaches and blood in I need to visit the doctor or is just possibly just a minor cold?

  • Hi Mesia. The presence of blood in any discharges or secretions should prompt you to seek medical attention. It may not be very serious but it is advisable to get medical advice.