Even if it is kind of gross when you're full of it and wrestling with it, phlegm actually serves a useful purpose: The thick, sludgy substance—made up of mostly water, salt, and antibodies—is designed ...

Congestion from cold and flu is the buildup of mucus in your nose, sinuses, or chest that causes a feeling of fullness or blockage. When you're dealing with congestion from a cold or the flu, you want ...

Medically reviewed by Sanja Jelic, MD Key Takeaways Drinking hot herbal tea can help soothe your throat and thin mucus. Using a humidifier can loosen mucus and clear chest congestion. Drinking clear ...