First Time User? Enroll now.
COVID-19: Vaccine information, visitor restrictions, testing, treatments and additional resources
Home > Fitness & Health > Health Library > Mucus
Mucus is a thick, slippery and usually clear substance that is produced in the lining of body cavities or canals, such as the nose, throat, sinuses, and airways of the lungs. Mucus protects and moistens the lining of body organs, such as the stomach and intestines, and traps dust particles, smoke, bacteria, and other irritants that enter the nose when a person inhales.
Mucus that becomes too thick and sticky can block the airway or digestive system or cause other problems in the body. Thick and sticky mucus is difficult for the body to remove and can increase the risk of infection.
Current as of: May 4, 2022
Author: Healthwise Staff
Medical Review:Adam Husney MD - Family Medicine & Patrice Burgess MD - Family Medicine & Kathleen Romito MD - Family Medicine & Donald R. Mintz MD - Otolaryngology
To learn more about Healthwise, visit Healthwise.org.
© 1995-2022 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Feeling under the weather?
Use our interactive symptom checker to evaluate your symptoms and determine appropriate action or treatment.
Our interactive Decision Points guide you through making key health decisions by combining medical information with your personal information.
You'll find Decision Points to help you answer questions about:
Get started learning more about your health!
Our Interactive Tools can help you make smart decisions for a healthier life. You'll find personal calculators and tools for health and fitness, lifestyle checkups, and pregnancy.