Spitting blood, medically termed hemoptysis, occurs when blood originates from the lower respiratory tract, such as the lungs or airways. This expulsion of blood or blood-tinged mucus signals that the delicate tissues lining the bronchi or lungs have been irritated or damaged. While often linked to minor issues, hemoptysis can also indicate a serious underlying medical condition. Therefore, it always warrants a professional medical evaluation to determine the source and cause, regardless of the amount of blood seen.
Differentiating the Blood Source and Appearance
The first step in evaluating this symptom is determining the true source of the bleeding, as blood expelled from the mouth may not be true hemoptysis. Respiratory tract blood is characteristically bright red, frothy, and mixed with sputum or mucus because it has been exposed to air. This differs from a nosebleed (epistaxis) or bleeding from the gastrointestinal tract.
Bleeding from the stomach (hematemesis) is typically dark, resembling coffee grounds, and mixed with food particles due to exposure to stomach acid. Hematemesis is often accompanied by nausea and vomiting, while true hemoptysis is usually associated with coughing. Observing the color, consistency, and accompanying symptoms helps pinpoint the origin of the blood.
Common Causes Originating in the Mouth and Throat
The most frequent causes of spitting blood are often the least severe, involving the upper respiratory tract or the oral cavity. Forceful coughing from a common cold or minor infection can rupture tiny capillaries in the throat or bronchial tubes. This results in small streaks of bright red blood or pink-tinged saliva mixed with mucus, known as mild hemoptysis.
Dental and gum issues, such as gingivitis or periodontitis, are a common source, causing gums to bleed easily after brushing or flossing. The blood mixes with saliva and is spit out, often leading to the mistaken belief that the blood originated in the lungs. Similarly, severe dryness or irritation in the throat, sometimes exacerbated by chronic mouth breathing, can cause superficial tears that bleed slightly.
Gastroesophageal reflux disease (GERD) is another frequent, non-pulmonary cause. Stomach acid travels up the esophagus, irritating the throat and vocal cords, which can lead to mild bleeding that mimics blood from the lungs. In all these instances, the amount of blood is typically very small and the bleeding is self-limiting.
Pulmonary and Systemic Conditions Requiring Diagnosis
While minor issues are common, hemoptysis can be a symptom of serious medical conditions affecting the lungs and circulatory system. Acute infections, such as bronchitis and pneumonia, are common causes where inflammation damages the airway lining and causes bleeding. The blood seen in these cases is usually small, appearing as rust-colored or bright red streaks in the phlegm.
Chronic lung diseases often cause hemoptysis due to structural changes in the airways and blood vessels. Bronchiectasis, where bronchial tubes are permanently damaged and widened, leads to chronic inflammation and makes arteries prone to rupture and bleeding. Conditions like Chronic Obstructive Pulmonary Disease (COPD) or cystic fibrosis also create ongoing inflammation that can erode into blood vessels.
More concerning causes include malignancies, as primary lung cancer can invade the airway and surrounding blood vessels, leading to bleeding. Cardiovascular conditions, such as pulmonary edema from congestive heart failure, increase pressure and rupture pulmonary capillaries, often resulting in pink, frothy sputum. A pulmonary embolism, a sudden blockage of a lung artery, can cause localized tissue death (infarction), resulting in the expectoration of blood.
When to Seek Emergency Medical Care
The presence of blood requires immediate emergency medical attention when the volume is significant or accompanied by other severe symptoms. Massive hemoptysis, defined as coughing up more than a few tablespoons of blood or any amount that compromises breathing, is a life-threatening emergency. The primary danger is not blood loss but the risk of asphyxiation, as blood can flood the airways and prevent oxygen exchange.
An emergency room visit is warranted if the blood is accompanied by severe shortness of breath, chest pain, dizziness, or fainting. Other warning signs include unexplained weight loss, night sweats, or expelled material that is dark, tarry, or resembles coffee grounds, suggesting a possible gastrointestinal bleed. Any bleeding that persists for more than a day or increases in frequency or volume should be evaluated urgently.