Coughing Up Phlegm

If you’re coughing up clear phlegm, it usually means your body is trying to flush out pollen, pet dander or other allergens. However, in some cases, it could indicate a more serious condition, such as:

Sputum Culture

A sputum culture is a test that checks for bacteria or another type of germ that may be causing a respiratory tract infection (an infection in your lungs or airways). Sputum, also known as phlegm, is a thick type of mucus made in your lungs. If you have an infection or chronic illness affecting the lungs or airways, sputum can settle in your lungs, and you may also cough it up

Sputum is not the same as spit or saliva. Sputum contains cells from your immune system that help fight bacteria, fungi, or other foreign substances in your lungs or airways. The thickness of sputum helps trap the foreign material. This allows cilia (tiny hairs) in the airways to push it through the mouth and be coughed out.

Sputum can be one of several different colors. The colors can help identify the type of infection you may have or check if a chronic illness has become worse. This helps your health care provider determine the best treatment. Sputum colors can include:

• Clear. This usually means you don’t have an infection, but large amounts of clear sputum may be a sign of lung disease.
• White or gray. This may also be normal, but increased amounts may mean lung disease.
• Dark yellow or green. This often means a bacterial infection, such as pneumonia. Yellowish-green sputum is also common in people with cystic fibrosis. Cystic fibrosis is an inherited disease that causes mucus to build up in the lungs and other organs.
• Black. This often shows up in people who smoke. It is also a common sign of black lung disease. Black lung disease is a serious condition that can happen if you have long-term exposure to coal dust.
• Brown or brown spots. This may be a sign of old blood. This can happen if you have cystic fibrosis, bacterial pneumonia, bacterial bronchitis, or some other lung diseases. It can also be caused by breathing in dust or other brown materials or toxins.
• Pink. This may be a sign of pulmonary edema, a condition in which excess fluid builds up in the lungs. Pulmonary edema is common in people with heart failure.
• Red. This may be an early sign of lung cancer. It may also be a sign of a pulmonary embolism (PE), a life-threatening condition in which a blood clot from a leg or other part of the body breaks loose and travels to the lungs. If you are coughing up red or bloody sputum, call 911 or seek immediate medical attention.

Other names: respiratory culture, bacterial sputum culture, routine sputum culture, bacterial culture, respiratory

What is it used for?

A sputum culture is most often used to:

• Find and diagnose bacteria or fungi that may be causing an infection in the lungs or airways
• See if a chronic illness of the lungs has worsened
• See if treatment for a lung or airway infection is working
• Help to diagnose respiratory conditions such as pneumonia, tuberculosis, and bronchiectasis

A sputum culture is often done with another test called a Gram stain. A Gram stain is a test that checks for bacteria at the site of a suspected infection or in body fluids such as blood or urine. It can help identify the specific type of infection you may have.

A sputum test is not usually used if your provider thinks you may have a viral infection.

Why do I need a sputum culture?

You may need this test if you have symptoms of pneumonia or another serious infection of the lungs or airways. These include:

• Cough which produces a lot of sputum
• Fever
• Chills
• Shortness of breath
• Chest pain that gets worse when you breathe deeply or cough
• Fatigue
• Confusion, especially in older people

Your provider may also order a sputum culture after an x-ray or other imaging tests show that you may have a lung infection. The sputum culture can help confirm this and determine the cause of the infection.

What happens during a sputum culture?

Your provider will need to get a sample of your sputum. During the test:

• You may be asked to rinse your mouth out with water before the sample is taken.
• Your provider will ask you to breathe deeply and then cough deeply into a special cup.
• A health care provider will ask you to breathe deeply and then cough deeply into a special cup.
• Your provider may tap you on the chest to help loosen sputum from your lungs.
• If you have trouble coughing up enough sputum, your provider may ask you to breathe in a salty mist to help you cough more deeply.
• If you still can’t cough up enough sputum, your provider may perform a procedure called a bronchoscopy. In this procedure, you’ll first get a medicine to help you relax, and then a numbing medicine so you won’t feel any pain.
• Then a camera attached to a thin, lighted tube will be put through your mouth or nose and into your airway. This helps your provider see the inside of your lungs and airway.
• Your provider will collect a sample from your airway using a small brush or suction.

Will I need to do anything to prepare for the test?

The test is often scheduled in the morning. To increase the amount of sputum, you may be encouraged to drink more water the night prior. You may also be asked not to eat for one or two hours before the test.

If you will be getting a bronchoscopy, you may be asked to fast (not eat or drink) for up to twelve hours before the test.

You may need to stop taking certain medicines before this test, so tell your provider about everything you take. Antibiotics may affect bacterial growth and the results of your sputum culture test. But don’t stop taking any medicines unless your provider tells you to.

Are there any risks to the test?

There is no risk to providing a sputum sample into a container. If you had a bronchoscopy, your throat may feel sore after the procedure.

If you had a bronchoscopy:

• Your throat may feel sore after the procedure
• It may take a few hours to be able to cough normally.
• You will not be permitted to eat or drink until you can cough normally again.

What do the results mean?

Your sputum sample will be put in a dish with a special substance that allows bacteria to grow. It usually takes a few days to get the results of your sputum culture, but it may take weeks. How long it takes to get your results will depend on the type of bacteria that you are being tested for, since some types of bacteria take longer to grow in the lab

If your results were normal, it means that no harmful bacteria or fungi were found.

If your results were not normal, it may mean you have some kind of bacterial or fungal infection. Your provider may need to do more tests to find the specific type of infection you have. The most common types of harmful bacteria found in a sputum culture include those that cause:

• Pneumonia
• Bronchitis
• Tuberculosis

An abnormal sputum culture result may also mean a flare-up of a chronic condition, such as cystic fibrosis or chronic obstructive pulmonary disease (COPD). COPD is a lung disease that makes it hard to breathe.

If you have questions about your results, talk to your provider. To understand the results of your sputum culture, your provider will consider your symptoms, medical history, and the results of other tests.

Is there anything else I need to know about a sputum culture?

Sputum may be referred to as phlegm or mucus. All terms are correct, but sputum and phlegm only refer to the mucus made in the respiratory tract (lungs and airways). Sputum (phlegm) is a type of mucus. Mucus can also be made elsewhere in the body, such as in the urinary or genital tract.

References

1. American Heart Association [Internet]. Dallas (TX): American Heart Association Inc.; c2024. Symptoms and Diagnosis of Venous Thromboembolism (VTE); [reviewed 2023 Nov 13; cited 2024 Mar 21]; [about 3 screens]. Available from: https://www.heart.org/en/health-topics/venous-thromboembolism/symptoms-and-diagnosis-of-venous-thromboembolism-vte
2. American Lung Association [Internet]. Chicago: American Lung Association; c2024. Coal Worker’s Pneumoconiosis (Black Lung Disease); [cited 2024 Mar 21]; [about 3 screens]. Available from: https://www.lung.org/lung-health-diseases/lung-disease-lookup/black-lung
3. American Lung Association [Internet]. Chicago: American Lung Association; c2024. Cystic Fibrosis (CF); [cited 2024 Mar 21]; [about 4 screens]. Available from: https://www.lung.org/lung-health-diseases/lung-disease-lookup/cystic-fibrosis
4. American Lung Association [Internet]. Chicago: American Lung Association; c2024. Pneumonia Symptoms and Diagnosis; [updated 2023 Aug 3; cited 2024 Mar 21]; [about 4 screens]. Available from: https://www.lung.org/lung-health-diseases/lung-disease-lookup/pneumonia/symptoms-and-diagnosis
5. Cleveland Clinic: Health Library: Symptoms [Internet]. Cleveland (OH): Cleveland Clinic; c2024. Coughing Up Phlegm; [reviewed 2023 Jan 20; cited 2024 Mar 26]; [about 7 screens]. Available from: https://my.clevelandclinic.org/health/symptoms/24636-coughing-up-phlegm
6. Cleveland Clinic: Health Library: Diagnostics and Testing [Internet]. Cleveland (OH): Cleveland Clinic; c2024.SputumCulture; [reviewed 2023 Aug 04; cited 2024 Mar 26]; [about 8 screens]. Available from: https://my.clevelandclinic.org/health/diagnostics/25174-sputum-culture
7. Mayo Clinic [Internet]. Mayo Foundation for Medical Education and Research; c1998-2024. COPD; [cited 2024 Mar 26]; [about 8 screens]. Available from: https://www.mayoclinic.org/diseases-conditions/copd/symptoms-causes/syc-20353679
8. National Heart, Lung, and Blood Institute [Internet]. Bethesda (MD): U.S. Department of Health and Human Services; Tests for Lung Disease; [cited 2022 Mar 24]; [about 9 screens]. Available from: https://www.nhlbi.nih.gov/health/lung-tests
9. Nemours Kids Health [Internet]. Jacksonville (FL): The Nemours Foundation; c1995-2024. Lungs and Respiratory System; [reviewed 2022 Jul; cited 2024 Mar 21]; [about 5 screens]. Available from: https://kidshealth.org/en/parents/lungs.html
10. Pathology Tests Explained [Internet]. Alexandria (Australia): Australasian Association for Clinical Biochemistry and Laboratory Medicine; c2024. Sputum culture; [reviewed 2023 Jun 01; cited 2024 Mar 26]; [about 6 screens]. Available from: https://pathologytestsexplained.org.au/ptests-pro.php?q=Sputum+culture
11. Shen F, Sergi C. Sputum Analysis. [Updated 2023 Feb 20; cited 2024 Mar 26]. [about 8 screens]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK563195/
12. Testing.com [Internet]. Seattle (WA): OneCare Media; c2024. Gram Stain; [modified 2021 Nov 9; cited 2024 Mar 21]; [about 9 screens]. Available from: https://www.testing.com/tests/gram-stain/
13. Testing.com [Internet]. Seattle (WA): OneCare Media; c2024. Sputum Culture, Bacterial; [modified 2020 Jan 14; cited 2024 Mar 21]; [about 14 screens]. Available from: https://www.testing.com/tests/sputum-culture-bacterial/
14. Very Well Health [Internet]. New York: About, Inc.; c2024. What Is Sputum?; [updated 2023 Aug 1; cited 2023 Mar 21]; [about 11 screens]. Available from: https://www.verywellhealth.com/what-is-sputum-2249192

Related Health Topics

• Antibiotics
• Bacterial Infections
• Breathing Problems
• Bronchial Disorders
• COPD
• Cough
• Cystic Fibrosis
• Fungal Infections
• Lung Diseases
• Pneumonia
• Tuberculosis

Coughing Up Phlegm

Coughing up phlegm is a normal symptom of colds and other health conditions. But coughing up phlegm without feeling sick could indicate a more serious underlying issue like heart or lung disease.

Overview

Certain health conditions, environmental factors and lifestyle factors can all contribute to coughing up phlegm.

What is coughing up phlegm?

Coughing up phlegm is a symptom of infections like the flu and common cold. Phlegm is a specific type of mucus that originates in your lungs and throat. It’s slightly thicker than the mucus that’s produced in your nose and sinuses. Another name for phlegm is sputum.

Most of the time, coughing up phlegm isn’t a cause for concern. It helps clear irritants and infections from your lungs. But if you cough up phlegm when you’re not feeling sick, it could mean you have a more serious underlying health condition. It can also tell you a lot about what’s going on with your body.

Possible Causes

What causes coughing up phlegm?

There are several health conditions — ranging from mild to severe — that can result in coughing up phlegm, including:

• Infections.
• Allergies.
• Asthma.
• GERD (chronic acid reflux).
• Lung diseases, such as COPD.

Certain environmental and lifestyle factors can contribute to coughing up phlegm, too, including:

• Smoking.
• Drinking beverages that contain caffeine or alcohol.
• Dehydration.
• Spending time in a dry environment.

What does it mean when you cough phlegm up?

Coughing up phlegm could mean different things depending on the color and consistency of the mucus. But you should always check with a healthcare provider if something doesn’t seem right.

Coughing up clear phlegm

If you’re coughing up clear phlegm, it usually means your body is trying to flush out pollen, pet dander or other allergens. However, in some cases, it could indicate a more serious condition, such as:

• Viral bronchitis.
• Viral pneumonia.

Coughing up yellow or green phlegm

This usually means your body is fighting off some sort of infection. People often develop yellow phlegm in the early stages, and it turns green the longer the infection lingers. Possible health conditions related to coughing up yellow or green phlegm include:

Coughing up white phlegm

White phlegm can mean a few different things, including:

• GERD.
• COPD.
• Viral bronchitis.
• Congestive heart failure. (If you develop heart failure symptoms, like shortness of breath, fatigue or leg weakness, call a healthcare provider immediately.)

Coughing up black phlegm

Another name for black phlegm is melanoptysis. Common causes include:

• Smoking.
• Breathing in coal dust or other dark materials or toxins.
• Exophiala dermatitidis, a type of fungal infection.

Coughing up brown phlegm or phlegm with brown spots

When you see brown phlegm, rust-colored phlegm or phlegm with brown spots, it usually indicates old blood. Common related conditions include:

• Bacterial bronchitis.
• Bacterial pneumonia.
• Cystic fibrosis.
• Lung abscess.
• Breathing in dust or other brown materials or toxins.

Coughing up bloody phlegm, red phlegm or pink phlegm

Coughing up bloody phlegm indicates a more serious issue. Common causes of red phlegm include:

• Pneumonia.
• Pulmonary embolism.
• Congestive heart failure. (Symptoms include pink, frothy phlegm, chest pain, sweating and shortness of breath.)
• Tuberculosis.
• Lung cancer.

If you cough up blood without phlegm, call a healthcare provider immediately or head to your nearest emergency room.

Care and Treatment

How do you stop coughing up phlegm?

Treatment depends on the underlying cause. For instance, if you’re coughing up phlegm as a result of allergies, your healthcare provider may recommend decongestants, antihistamines or corticosteroids. If you have an infection, your provider may prescribe antibiotics. If GERD causes you to cough up phlegm, then you might need antacids or other medications that relieve acid reflux symptoms.

Your cough may go away on its own in a few days. But if you’ve been coughing up phlegm for two weeks or more and your symptoms haven’t improved, schedule an appointment with a healthcare provider.

Are there things I can do at home to encourage coughing up phlegm?

Coughing up phlegm helps rid your body of allergens, irritants and infections. Here are some recommendations on how to cough up phlegm:

• Use a humidifier. Keeping the air in your home moist can help loosen phlegm in your lungs so you can cough it up easier.
• Stay hydrated.Drink plenty of water to help thin out mucus and prevent dehydration.
• Gargle with saltwater. Add 1/2 tablespoon of salt to a glass of warm water. Gargle to loosen any phlegm.
• Take over-the-counter expectorants. Expectorants (like Mucinex®) thin your mucus so it’s easier to cough up.
• Use eucalyptus oil. Products containing eucalyptus oil (like Vicks® VapoRub™) can help loosen phlegm in your chest. Use these products exactly as described on the label.

When To Call the Doctor

When should I see my healthcare provider?

You should schedule an appointment with a healthcare provider if:

• Your cough lasts for more than two weeks.
• You’re coughing up phlegm that’s not clear in color.
• You have a fever.
• You’re wheezing or having difficulty breathing.

Additional Common Questions

Is coughing up phlegm a good thing?

Yes. While the presence of mucus may indicate an underlying issue, coughing up phlegm is a good thing because it helps clear irritants, allergens and infections out of your system.

Is coughing up phlegm a symptom of COVID-19?

Currently, research suggests that most people who get COVID-19 develop a dry cough. However, as the virus worsens, some people may notice an increase in mucus production and may cough up phlegm as a result.

When should I be worried about coughing up phlegm?

Coughing up phlegm is a good thing. But if your cough lasts longer than two weeks or if the phlegm is yellow, green, brown, black, white or red, you should schedule an appointment with a healthcare provider as soon as possible.

If you’re coughing up blood without phlegm, call a healthcare provider right away or go to your nearest emergency room.

A note from Cleveland Clinic

Coughing up phlegm is unpleasant. Examining it, even more so. But phlegm can tell you a lot about what’s going on inside your body. If you cough up phlegm that’s yellow, green, brown, black, white or red — or if you cough up mucus for two weeks or longer, schedule a visit with your healthcare provider. They can find out what’s causing you to cough up phlegm and treat any underlying conditions.