Seeing blood emerge from your mouth is alarming, ranging from a faint streak mixed with saliva to a significant volume of liquid or clotted material. While the severity varies widely, any unexplained bleeding requires careful investigation to determine its precise source and cause.
Differentiating the Source of Bleeding
The physical characteristics of the blood provide the first clues about its origin. Blood coughed up from the lungs (hemoptysis) typically appears bright red or pink and is often frothy because it is mixed with air and mucus. This expulsion is usually preceded by coughing or deep throat clearing.
Conversely, blood originating in the stomach or upper gastrointestinal (GI) tract and then vomited (hematemesis) often looks different. Stomach acid reacts with the blood’s hemoglobin, causing it to darken into a dark red, brown, or granular texture resembling coffee grounds. Hematemesis is usually accompanied by nausea and forceful vomiting.
Blood originating in the mouth or throat is generally mixed only with saliva and is often less voluminous. This type of bleeding is frequently noticed when spitting, upon waking, or during routine dental care. Distinguishing between these three sources directs attention toward the respiratory system, the digestive system, or the oral cavity.
Common Causes Originating in the Mouth and Throat
The most frequent causes of blood in the mouth relate to the oral cavity and are generally the least threatening. Gingivitis and periodontal disease are primary culprits, causing gums to become inflamed, tender, and prone to bleeding, especially during brushing or flossing. Minor trauma, such as accidentally biting the cheek, lip, or tongue, can also create a small wound that bleeds conspicuously when mixed with saliva.
Bleeding can also occur temporarily after certain dental procedures, such as a tooth extraction or a deep dental cleaning. Though usually resolving within a few hours, this bleeding can seem excessive when mixed with saliva. Sometimes, the blood originates from a posterior nosebleed (epistaxis), running down the back of the throat before being spit out.
Severe or prolonged coughing can irritate or slightly tear the delicate lining of the throat and upper airways, producing small streaks of blood mixed with mucus. This minor bleeding is often confused with bleeding from the lungs. Certain medications, particularly blood thinners, can also increase the likelihood and duration of bleeding from any minor oral abrasion or inflamed gum tissue.
Serious Causes from the Lungs (Hemoptysis)
When blood is coughed up from the respiratory tract, causes range from common infections to serious pulmonary conditions. Acute and chronic respiratory infections, including severe bronchitis and bacterial pneumonia, are frequent reasons for hemoptysis. The persistent inflammation and forceful coughing associated with these conditions can damage small blood vessels within the airway lining.
Tuberculosis (TB) remains a cause, as the infection creates cavities and erodes tissue within the lungs, leading to bleeding. A pulmonary embolism (PE), a blockage of a lung artery, is another possibility. PE can cause localized tissue damage and the coughing up of blood, often accompanied by sudden shortness of breath and chest pain.
Conditions causing high pressure in the lung blood vessels, such as pulmonary edema resulting from severe heart failure, may also lead to blood-tinged sputum. Lung cancer must be considered, particularly in smokers or older adults, as a tumor can erode into a major airway or blood vessel. Even small amounts of coughed-up blood warrant a medical evaluation, especially if the bleeding is recurrent or accompanied by other respiratory symptoms.
Serious Causes from the Digestive Tract (Hematemesis)
Bleeding originating in the upper gastrointestinal tract (hematemesis) indicates a significant breach in the lining of the esophagus, stomach, or upper small intestine. The dark, coffee-ground appearance is a hallmark sign, resulting from the oxidation of blood by stomach acid. A common serious cause is a peptic ulcer, an open sore in the stomach or duodenum that erodes into a blood vessel.
Another source is severe inflammation of the stomach lining (gastritis), which can lead to superficial bleeding aggravated by factors like excessive alcohol consumption or prolonged use of nonsteroidal anti-inflammatory drugs (NSAIDs). Forceful or repeated vomiting can cause a Mallory-Weiss tear, a longitudinal laceration in the mucous membrane of the lower esophagus. These tears often cause significant, bright red bleeding upon vomiting.
A potentially life-threatening cause is the rupture of esophageal varices, which are enlarged, fragile veins in the lining of the lower esophagus. Varices develop in people with severe liver disease, such as cirrhosis, where restricted blood flow backs up into the esophageal veins. Hematemesis is often accompanied by severe abdominal pain, lightheadedness, or signs of shock, indicating a high volume of blood loss.
Immediate Action and Medical Triage
Determining the appropriate next step depends on the volume and nature of the blood. If the bleeding is minor and appears only after aggressive brushing, flossing, or minor oral trauma, monitor the situation. Schedule an appointment with a dentist or doctor if it persists beyond a day. For minor bleeding, gentle rinsing and applying pressure with clean gauze can help.
Certain signs signal a medical emergency requiring immediate attention by calling emergency services or going to the nearest emergency room. These warning signs include:
- Vomiting large amounts of blood.
- Any instance of blood that looks like coffee grounds.
- Heavy, persistent bleeding that cannot be stopped.
- Bleeding accompanied by chest pain, severe dizziness, shortness of breath, confusion, or a rapid heart rate.
These symptoms may indicate significant internal blood loss or respiratory compromise.