Seeing blood when you cough or spit can be scary. Even a little blood can make your heart beat fast and make you think of the worst.
Coughing or spitting up blood, called hemoptysis, can happen for many reasons. Some reasons are minor and easy to treat, while others need urgent medical help.
“Blood in your saliva can come from your lungs, throat or even your nose,” said Samia Kadri, a family nurse practitioner at Banner Urgent Care. “Most reasons for this are not serious and can be treated. But it’s important to see a health care provider."
If you see blood in your spit, learn what might cause it, what signs to watch for and when to go see a health care specialist.
Common causes of spitting up blood
1. A bad cough or respiratory infection
One common cause is irritation from coughing hard or a lot. Persistent coughs can sometimes break small blood vessels in the throat or lungs, leading to blood in your spit.
“Blood-streaked mucus can happen with upper respiratory infections or bronchitis (an infection of the airways in the lungs) and is usually not life-threatening,” Kadri said.
Bronchitis can last a few weeks or be a long-lasting (chronic) illness. This lung problem often causes coughing that brings up mucus mixed with blood.
Other causes may be:
- Pneumonia (a lung infection)
- A bad cold or flu
- COVID-19
2. Nosebleeds
Blood may come from the nose rather than the lungs.
“If you have dry nasal passages from a cold or seasonal allergies, a small nosebleed can drip down your throat and appear when you spit,” Kadri said.
Applying manual pressure to stop a nosebleed is usually safe. If the bleeding keeps happening or you don’t know why it’s happening, see your health care provider right away.
3. Gum disease or mouth irritation
Dental problems such as bleeding gums and mouth sores, or brushing and flossing too hard, can cause minor bleeding in the mouth that mixes with saliva. This is more common if you see blood but aren’t coughing.
Learn more about how the health of your mouth affects your whole body.
4. Stomach or esophagus issues
Blood from the stomach or esophagus can sometimes appear in your saliva. This may be caused by:
- Acid reflux (GERD)
- Stomach ulcers
- Severe vomiting
- Tears in the esophagus
“Irritating foods, like spicy dishes, or alcohol and NSAIDs (ibuprofen) use can also contribute to stomach lining irritation and bleeding,” Kadri said.
This blood often looks darker and may be mixed with food.
5. Chronic or less common conditions
Certain long-term or serious health issues can lead to spitting up blood:
- COPD (chronic obstructive pulmonary disease): A long-term lung disease that makes breathing difficult.
- Cystic fibrosis: A genetic disease that causes thick mucus to build up in the lungs.
- Tuberculosis (TB): A bacterial lung infection that can damage lung tissue.
- Bronchiectasis: Damage to the airways that leads to chronic coughing and mucus buildup.
6. Blood clots in the lungs
A pulmonary embolism is a blood clot that travels to the lungs. This is a medical emergency.
Symptoms may include:
- Sudden shortness of breath
- Chest pain
- Fast heart rate
- Coughing up blood
7. Lung cancer
In some cases, coughing up blood can be a sign of lung cancer. This is more likely if you:
- Smoke or used to smoke
- Are over age 40
- Have ongoing symptoms like weight loss or chest pain
While this cause is less common, it’s one reason health care specialists take this symptom seriously.
How the blood looks and what it means
Not all blood in spit looks the same. Watching the color and how much can help your health care provider identify the source:
- Bright red: Usually from the lungs or throat
- Pink or frothy: Mixed with mucus from the lungs
- Dark, coffee-colored: Often from the stomach or esophagus
When to seek medical attention
Blood in your spit is more serious when it comes with other symptoms. Kadri urges you to seek emergency care if you notice:
- Shortness of breath or difficulty breathing
- Chest pain or tightness
- Large amounts of blood (over half a cup in 24 hours)
- Dizziness, fainting or rapid heartbeat
- Vomiting blood
“Any airway compromise, like trouble breathing, necessitates immediate evaluation by emergency personnel,” Kadri said.
See your health care provider if:
- You cough up blood more than once
- The bleeding keeps coming back
- You have a fever, night sweats or weight loss
- You smoke or have a lung condition
- You’re not sure where the blood is coming from
- You had a recent injury or accident
How specialists figure out the cause
“Health care specialists use a careful combination of history, imaging and scope evaluations to help determine whether the bleeding is minor or life-threatening,” Kadri said.
Tests may include:
- Chest X-ray or CT scan
- Blood tests
- Sputum (mucus) tests
- An endoscope to look at your airways or stomach
You may also see the following specialists:
- Ear, nose and throat (ENT) specialist
- Gastroenterologists
- Pulmonologists
Can coughing or spitting up blood be prevented?
Not all causes can be prevented, but you can lower your risk by:
- Not smoking or vaping
- Treating infections early
- Managing chronic conditions like asthma or COPD
- Using a humidifier and moisturizing nasal sprays if dry air causes nosebleeds
- Wearing protective gear if exposed to chemicals or dust
- Brush and floss gently to avoid gum bleeding
Bottom line
Coughing or spitting up blood can be alarming, but it doesn’t always mean something serious. Still, it’s a symptom that deserves attention.
Small amounts may come from irritation or infection. Larger amounts, ongoing bleeding or other symptoms need medical care right away.
If you are unsure, trust your instincts and reach out to a health care provider or Banner Health specialist. Getting an answer can bring peace of mind and help you get the care you need.
