Mucus secretion

Mucus secretion is the production of thick, slimy fluid from the mucous membranes. It can range from clear and watery to thick and sticky. It is usually accompanied by coughing or sneezing. It can be a sign of an infection or an allergic reaction, and can also be caused by irritation to the airways. It can manifest as a runny nose, chest congestion, or post-nasal drip. It typically develops gradually, becoming more severe over time.