What It Means and How To Get Rid of It

Coughing up thick, green mucus may indicate a bacterial or, less often, viral infection, but that’s not always the case. You constantly breathe in bacteria, some of which are harmless, through your nasal passages. A build-up of bacteria may cause green mucus without making you sick.

Antibiotics only treat bacterial infections, but your mucus color alone cannot tell whether an infection is bacterial or viral.

Green or yellow mucus, especially if it’s thick and sticky, can sometimes signal an infection. Bacteria and viruses cause inflammation in your nasal passages, leading to excess mucus.

Your mucus is generally clear, “but some mild coloration is not typically cause for alarm,” Philip Chen, MD, an associate professor of otolaryngology and rhinology at the University of Texas Health Science Center at San Antonio, told Health.

You constantly breathe thousands of bacteria into your nasal passages, which may cause mild coloration of your mucus. These bacteria do not always make you sick.

Some conditions and environmental factors are more closely linked to some mucus colors than others. Certain mucus colors may indicate the following:

• Brown: Dried blood or inhaling something brown, such as dirt or cigarette smoke, may cause brown mucus. You may notice brown mucus if small amounts of blood are in your nasal passages or the air is dry. Brown mucus is typically normal and not harmful.
• Black: This can result from inhaling something dark, such as dust or cigarette smoke. Black mucus may be a symptom of a fungal infection in rare cases.
• Pink or red: Blood is the primary reason if your mucus is pink or red. An injury to your nose or too much friction from blowing or rubbing your nose may be the culprit. Pink or red mucus may also result from dry air.

Neutrophils, or white blood cells, help your body fight off infections. These cells release chemicals in response to bacteria or viruses, which may cause mild coloration in your mucus.

Your body gets rid of white blood cells and bacteria or viruses through your mucus. White blood cells may cause yellow mucus. Green mucus typically results when there is a large number of white blood cells and other debris.

Viral vs. Bacterial Infection

Green or yellowish-green mucus is one of the telltale signs your body is working to get rid of germs that cause infections. The infectious agent may be bacteria, like those that cause sinus infections. Viruses may cause sinus infections, but they typically cause clear or, less often, light yellow mucus.

Viruses that may cause yellowish-green mucus include:

• Coronaviruses, like SARS-CoV-2, which causes COVID-19
• Flu viruses
• Rhinoviruses, which are responsible for most cases of the common cold

Mucus that’s cloudy and more yellow than green may be likelier to be the result of a cold. The color of your mucus alone cannot tell you whether your infection is bacterial or viral if you are sick.

Most infections that cause green mucus clear on their own. You may contact a healthcare provider if you have symptoms like:

• A cough that lasts more than 10 days or brings up mucus that’s gray or yellow-green
• Fever
• Mucus that has a foul odor or only leaves one nostril
• Nasal congestion that causes blurry vision or swelling of the cheek, eyes, forehead, or side of the nose 
• Symptoms that last more than three weeks
• Throat pain
• White or yellow spots on the tonsils or parts of the throat

You may be able to get rid of green mucus if you treat a runny or stuffy nose. To do this at home, you may try to:

• Apply a warm washcloth to your face
• Drink plenty of clear fluids
• Inhale steam or using a humidifier
• Lie with your head elevated when you sleep
• Take medicines, such as antihistamines or decongestants, to ease symptoms
• Use adhesive strips that you apply to your nose
• Use a nasal wash to clear away mucus 

You might not always be able to prevent green mucus. It’s still possible to take steps to prevent a bacterial or viral infection that causes it, such as:

• Clean and disinfect objects and surfaces that people frequently touch, such as countertops and doorknobs
• Regularly wash your hands with soap and water for at least 20 seconds
• Stay away from people who are sick
• Use a hand sanitizer with at least 60% alcohol if you do not have soap or water

You likely do not need to see a healthcare provider if you have green mucus but otherwise feel fine. Other symptoms, like body aches, fever, and a runny or stuffy nose, may signal an infection.

You can typically treat green mucus at home. Apply a warm washcloth to your face, drink plenty of fluids, and inhale steam to get rid of nasal congestion. Consult a healthcare provider if your symptoms do not go away or worsen.