It differs from saliva, which is produced higher up in the mouth.
The quantity, texture, andcolor of sputumcan help to diagnoselung cancerand other medical conditions that affect sputum production.
This article explains what sputum is and what it looks like.
Illustration by Julie Bang for Verywell Health
It also discusses what different colors of sputum might indicate.
It works with small structures in the airway called cilia to trap and remove foreign substances.
Sputum isnotthe same as saliva, a substance secreted in the mouth to help with digestion.
Verywell / Cindy Chung
The terms sputum and phlegm are used interchangeably.
The term “mucus” may sometimes be used instead of sputum.
It involves inhaling a mist of ProAir (albuterol) followed by saline to make sputum production easier.
These types of white blood cells are attracted to the site of bacterial infections and may cause green sputum.
Brown sputum can indicate:
Sputum may also appear brown or black due to the presence of old blood.
Even a teaspoon of coughed-up blood is considered a medical emergency.
Coughing up 1/4 cup of blood is considered massive hemoptysis and carries a poor prognosis.
When the cilia can’t move sputum towards your mouth, it accumulates in the airways.
Quitting smoking is the best way to combat this problem.
How Do you Flush Out Phlegm?
An increased amount of sputum is often the body’s attempt to protect and heal damage to the airways.
Contact your healthcare provider if you have chronic or concerning symptoms.
An accurate diagnosis may lead to earlier treatment and improved outcomes.
2017;4(1):e000236.
2019;7(15):358. doi:10.21037/atm.2019.04.91
Davidson K, Shojaee S.Managing massive hemoptysis.Chest.
2019; doi:10.1016/j.chest.2019.07.012
Budzinski T.Chronic bronchitis.Contemporary Clinic.
Redondo M, Keyt H, Dhar R, Chalmers JD.Global impact of bronchiectasis and cystic fibrosis.Breathe.
