It’s actually common for mucus to change from clear to white, yellow, or green during a single illness. This progression is due to changes in the immune response as days pass and what’s mixed with the mucus itself.
In some cases, a change in mucus color may not require you to do anything but seek at-home or over-the-counter treatments to ease other symptoms, if needed. In others, it may be a sign of a health problem that needs medical treatment.
This article walks you through the various colors your mucus can take on—clear, white, yellow, green pink, red, orange, brown, and black—and their possible causes. It also helps you determine if it’s time to see a healthcare provider.
Clear Mucus
Healthy, normal mucus is clear and made up of water, salt, proteins, and antibodies. Your body makes it night and day to protect your nasal passages, putting out about 1.5 quarts daily.
You may have an especially runny nose with clear mucus:
During the early stages of a cold or other viral illness Due to allergies (allergic rhinitis) As a result of nonallergic rhinitis, which is especially common during pregnancy
White Mucus
White mucus is often associated with a cold or other infection that causes a stuffy nose. When you’re congested, inflammation in your nose makes it harder for the snot to flow out, and it starts to dry. This makes it cloudy and thick.
Nausea and/or vomiting Stiff neck Light or noise sensitivity Headaches that get better or worse with a change in position
It may also turn white due to the presence of immune cells that your body sends to battle the illness.
Yellow Mucus
Yellow mucus means your illness is progressing normally. White blood cells and other cells from the immune system have come to fight the germs making you sick. Some of them are now exhausted and being washed away by mucus.
The texture of yellow mucus is likely drier and thicker than it used to be as well.
Yellow mucus may also mean you have allergies. Allergens irritate the nasal passages, which can lead to the production of thick, pale yellow phlegm that runs down the back of the throat and causes coughing.
Green Mucus
Green, thick snot means your body is fighting a hard battle. Even more depleted immune cells and waste products are being flushed out.
Green mucus isn’t a reason for immediate concern. But if you’re still sick after about 12 days, you could have a bacterial infection and might need antibiotics. Especially if you have a fever or nausea, it’s time to see a healthcare provider.
Pink or Red Mucus
When you have pink or red mucus, it means there’s blood in your nose. This can be caused by:
People with severe COVID-19 who develop acute respiratory distress syndrome (ARDS) may have a buildup of phlegm in the lungs. This mucus is thick and concentrated and cannot be coughed up like the phlegm that’s related to the flu or common cold.
Blowing your nose a lotPicking your noseGetting hit in the noseDry nasal passages due to illness or weatherPregnancy
Blood in the nose is more common if you live in a dry climate or at a high elevation. Having asthma or allergies can also cause blood in your nose. A constantly runny nose can irritate nasal passages and cause one of the tiny capillaries in your nose to burst.
If you’ve had some sort of trauma to your nose or face, such as a car accident, you should see a healthcare provider right away. Other reasons to seek medical help include:
Prolonged bleeding for more than 30 minutesHeavy bleeding, or more than a tablespoon of bloodDifficulty breathing with a bloody nose
Brown or Orange Mucus
Brown mucus could result from dried blood getting mixed in. Mucus can also turn brown or orange if you inhale something like dirt, a red spice such as paprika, or tobacco (snuff).
This color doesn’t typically result from illness.
Black Mucus
Black mucus is rare and means you should see a healthcare provider right away. It is often a sign of a fungal infection that needs to be treated. These infections can cause serious symptoms and some forms require surgery.
Most healthy people aren’t susceptible to these infections. They’re more common, although still somewhat rare, in people with an immune system that’s weakened due to illness or medication.
Other potential causes of black snot are:
Cigarette smokingUse of illegal drugs
Don’t just assume you have black snot because you’re a smoker, though. Not only can a fungal infection be dangerous, it could be a sign that you have an undiagnosed autoimmune disorder, so get medical attention.
When Should You Be Concerned?
If you have congestion with the following symptoms, it may be time to get evaluated:
Severe symptomsSymptoms that persist for more than two weeksStarting to feel better and then getting sick again, usually with a cough and a temperature above 102 degrees F. These are signs of a secondary infection (such as a bacterial infection after a virus). Yellow mucus or green mucus for longer than two weeks accompanied by pain and pressure in your sinuses and face. These symptoms may indicate a sinus infection.
Your healthcare provider can determine what over-the-counter or prescription medicine is best to help relieve your symptoms.
While mucus is associated with bacteria, it’s important to remember that bacteria are present in your body all the time. Some make you sick and some don’t. Just because they’re in your mucus doesn’t necessarily mean they’re problematic—or that you need antibiotics to get better. For example, bacterial infection only occurs in between 0.5% and 2% of rhinosinusitis cases. Many sinus infections go away on their own without antibiotics, but some do require treatment.
Summary
Changes in mucus color, from clear to white to yellow to green, are part of the normal course of an illness. It’s a sign that your immune system is fighting to get better.
Pink, red, orange, or brown mucus, on the other hand, is typically not from an illness. It may just mean that there is blood or dried blood in your nose. If you have black mucus, which is rare, it may signal a fungal infection and you need to see a healthcare provider.
A Word From Verywell
Healthcare providers don’t often make a diagnosis based solely on the color of mucus, but it can help complete the picture. So while it’s useful to tell your healthcare provider if your mucus has changed color and consistency, don’t expect to automatically get antibiotics just because it’s green. Your healthcare provider will use all the information at their disposal to determine the best course of action.
