Phlegm is a form of respiratory mucus produced by the lungs. The airways between the larynx and the respiratory bronchioles are lined by columnar epithelium over which an airway surface liquid (ASL) ...

Most people are all too familiar with the icky, uncomfortable feeling of having mucus build up in the nasal passageways while suffering through a cold or bad allergy flare-up. Or is it phlegm, rather ...

People often dismiss a cough as a minor ailment, but sometimes it can be a sign of an underlying problem, especially when ...

Mucus isn't exactly something people give much thought to — until they're sick and dealing with a constantly runny nose. But mucus is actually an important part of a healthy immune system, according ...

Healthy phlegm is usually clear and runny, but many different health conditions can change the consistency or color. Phlegm, also called sputum, is mucus produced by your lungs that helps protect your ...

When you're sick you'll often produce more phlegm, and might notice it's thicker or a different color: white, green, yellow or maybe even brown. We all produce mucus, even when healthy. Mucus is a ...

The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their ...

Although mucus and phlegm are related terms, they don't mean exactly the same thing. Karl Tapales via Getty Images Most people are all too familiar with the icky, uncomfortable feeling of having mucus ...