Drinking plenty of fluids can help decrease the thickness of phlegm and make it easier to remove. Bloody, brown, white, yellow, or green phlegm may be a sign of an underlying condition or infection.

Mucus is a thin, slippery fluid that lines the nose, throat, and other passages to trap dust and germs. Phlegm is a thicker type of mucus produced in the lungs to catch and remove harmful particles ...