The main component of nasal mucus is water. It is combined with proteins, sodium, cells, and other substances, helping to keep the nasal passages moist. When suffering from rhinitis, colds, or similar conditions, the nasal mucosa secretes a large amount of mucus to expel pathogens or allergens. Usually transparent, but the amount, viscosity, and color can vary depending on the underlying cause.

 

◇Yellow nasal discharge

 

Yellow mucus indicates that the immune system is actively fighting an infection. White blood cells sent to attack the infectious agent die and release enzymes that give mucus a yellowish color. This is a symptom that appears when viruses such as the common cold, influenza, or respiratory syncytial virus (RSV) invade the body.

◇Green nasal discharge

 

Green mucus appears when the immune response becomes stronger. The reason it appears green is due to an enzyme called myeloperoxidase, produced by a type of white blood cell called neutrophils. This enzyme creates specific molecules that destroy pathogens. It mostly occurs when infected with bacteria, but can also happen when the immune response is particularly strong against aggressive viruses.

 

◇Red and pink

 

It means that blood is mixed with mucus. This occurs when the nasal tissue is irritated or damaged. For example, excessive nose blowing or picking the nose when the nasal mucosa is dry can cause injury to the internal tissue. If a small amount of blood stops quickly, there is generally no need to worry. The same applies to brown or orange nasal discharge.

 

◇Black

 

Black mucus can indicate a serious problem unless it has been exposed to dirt, smoke, or other substances for a long period. For example, a person with a weakened immune system infected with mold may develop black nasal discharge.

Meanwhile, if you are suffering from excessive nasal mucus, taking an antihistamine can help alleviate the symptoms. When histamine irritates the nasal mucosa, it causes nasal discharge, but antihistamines suppress the action of histamine to reduce the runny nose. When the nasal mucus is severe, using a suction device at an ENT clinic to remove the mucus is also an option.

 

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Runny nose is usually clear-colored in cases of rhinitis.

I believe a cold is associated with yellow color.

 

Depending on the health of your runny nose

Are there so many different colors?