Can COVID Cause Coughing Blood?
Coughing up blood can feel alarming, especially when linked to an illness like COVID-19. While most people with COVID-19 experience common symptoms such as fever, cough, and fatigue, a small number may notice blood in their mucus or sputum. Yes, COVID-19 can cause someone to cough up blood, but it is an uncommon symptom often tied to complications in the lungs.
This symptom may occur when the infection leads to inflammation, pneumonia, or damage to delicate blood vessels in the airways. In some cases, secondary infections or pre-existing lung conditions can make the problem worse. Other factors like dry air or irritation can also play a role.
Definition of Symptom
Coughing up blood, also called hemoptysis, means there is blood in mucus or phlegm that comes from the lungs or airways. It can appear as streaks of blood mixed with spit or as larger amounts within thick mucus.
This symptom is different from bleeding that starts in the nose or mouth. When blood originates from the respiratory tract, it usually appears with a cough and may be mixed with phlegm. Common features of hemoptysis include:
- Blood-streaked mucus after coughing
- Bright red or rust-colored phlegm
- Small clots or streaks of blood in spit
The amount of blood can vary. Mild cases may only show small streaks, while more serious cases involve larger quantities. Even small amounts should not be ignored, as they may signal irritation, infection, or other lung conditions.
In COVID-19, hemoptysis is uncommon but has been reported. Most people with the virus develop a dry cough, but sometimes inflammation or lung damage leads to bloody mucus. The symptom should be distinguished from other causes, such as bronchitis, pneumonia, or lung injury. A simple way to understand the difference:
| Symptom | Typical Appearance | Possible Source |
|---|---|---|
| Hemoptysis | Blood mixed with phlegm | Lungs or airways |
| Nosebleed Drainage | Bright red blood without mucus | Nasal passages |
| Gum Bleeding | Blood in saliva | Mouth or gums |
Possible Causes/Diseases Condition
Coughing up blood, also called hemoptysis, can sometimes appear in people with COVID-19. While not common, it may happen when the infection causes damage or irritation in the lungs or airways.
COVID-19 pneumonia is one of the main causes. The virus can inflame lung tissue, leading to bleeding in small blood vessels. This bleeding may mix with mucus and appear when a person coughs. Other lung conditions can also raise the risk. For example:
- Asthma and bronchitis can irritate airways and cause streaks of blood in mucus.
- Chronic obstructive pulmonary disease (COPD) may worsen during infection, sometimes leading to bleeding.
- Tuberculosis (TB) is another serious disease that can cause coughing up blood and may be mistaken for COVID-19 symptoms.
Some people with long COVID continue to experience lingering cough. In rare cases, airway irritation from a long-term cough may lead to small amounts of blood in sputum. The table below shows possible related conditions:
| Condition | How it may cause blood when coughing |
|---|---|
| COVID-19 Pneumonia | Inflames lung tissue and blood vessels |
| Asthma | Irritates airways during flare-ups |
| Bronchitis | Causes airway inflammation and mucus with blood |
| COPD | Worsens with infections, may lead to bleeding |
| TB | Infects lungs, often linked to hemoptysis |
| Long COVID | Persistent cough may irritate airways |
Other Non-Disease Causes
Not all cases of coughing up blood come from infections or lung disease. Certain habits, treatments, and body responses can also play a role.
- Smoking is one of the most common non-disease factors. Long-term smoking irritates the airway lining and weakens small blood vessels, which may cause streaks of blood in mucus when coughing.
- A weakened immune system can make the lungs more sensitive, even without an active infection. People undergoing treatments like chemotherapy often experience fragile airways that may bleed more easily when irritated.
- Some medications may also contribute. For example, overuse of a cough suppressant can keep mucus trapped, leading to harder coughing later. This forceful coughing may rupture small blood vessels in the throat or chest.
The table below highlights some non-disease causes:
| Cause | How It Can Lead to Blood in Cough |
|---|---|
| Smoking | Irritates airways, damages vessels |
| Weakened immune system | Makes tissues fragile and slow to heal |
| Chemotherapy | Increases airway sensitivity and bleeding risk |
| Cough suppressant use | Leads to forceful coughing after buildup |
- Environmental factors such as dry air or exposure to dust can also irritate the throat. In these cases, blood usually appears in small amounts and clears once the irritation stops.
These causes are not diseases themselves, but they can still make coughing up blood more likely when the lungs or airways are under stress.
How It Causes the Symptom
COVID-19 affects the lungs and airways, which can sometimes lead to coughing up blood. Infection or inflammation can damage small blood vessels in the respiratory tract. Frequent coughing may also cause tiny breaks that allow blood to mix with mucus.
Severe cases, such as those involving pneumonia, may injure lung tissue. When this happens, blood may appear in the sputum along with other symptoms like fever, fatigue, or chest pain. These signs often point to a more serious infection that needs medical evaluation.
The virus can also trigger an intense immune response, inflaming the lining of the airways and making them more fragile. As a result, even a dry, persistent cough can produce streaks of blood. Other symptoms like a sore throat or shortness of breath may appear at the same time. These do not directly cause bleeding but can add to the strain on the airways. Possible factors that increase risk:
- Severe or prolonged coughing
- Lung complications such as pneumonia
- Fragile blood vessels in the airways
- Co-existing health conditions affecting the lungs
| Symptom | How it relates to coughing up blood |
|---|---|
| Fever | Signals infection that may damage lung tissue |
| Fatigue | Suggests the body is under stress from illness |
| Chest pain | May indicate lung inflammation or strain |
| Sore throat | Adds irritation but less often linked to bleeding |
Possible Complications
Coughing up blood with COVID-19 is uncommon but can signal more serious problems. Sometimes, it points to lung infections such as pneumonia, which can damage airways and increase bleeding risk. Severe inflammation may also cause breathing difficulties or lung scarring. These conditions make breathing harder and may require hospital care.
COVID-19 can also increase the risk of blood clots, which may block blood flow in the lungs and lead to bleeding. If bleeding is heavy or persistent, doctors may use procedures to locate or stop the source, such as a scope to look inside the airways or a treatment to block affected blood vessels. Possible complications linked to coughing up blood in COVID-19:
- Pneumonia or secondary infections
- Breathing problems or lung scarring
- Blood clots in the lungs
- Airway damage or irritation
- Need for medical procedures to control bleeding
People with underlying conditions may face higher risks of these complications, making early medical attention important.
When to Seek Medical Attention
Coughing up blood, even in small amounts, should not be ignored. While mild irritation can sometimes cause it, coughing up blood may also signal a more serious condition, including complications linked to COVID-19. Seek immediate medical care if you notice:
- Large amounts of blood in your cough
- Ongoing or worsening bleeding
- Chest pain or tightness
- Shortness of breath or difficulty breathing
- Fever, weakness, or unexplained weight loss
If you see a small streak of blood in your mucus, you may not need to visit the emergency room, but you should still call your healthcare provider. Your doctor can find out if the bleeding comes from an infection, inflammation, or another issue.
If you have COVID-19 and start coughing up blood along with low oxygen levels, severe cough, or trouble breathing, go to the emergency department right away. These symptoms can point to lung problems that need urgent care.
Coughing up blood may come from infections, chronic lung disease, or other conditions not related to COVID-19. Because the causes vary, only a medical professional can give the right diagnosis and treatment.
