What is Congestion?

Congestion refers to the stuffiness or fullness patients experience in the nasal or breathing passageways and in the sinuses when they get sick⁴. Nasal and sinus congestion is usually caused by increased blood volume in the vessels that line that passage of the nose⁴. This increase happens because white blood cells rush to the area to defend you. This narrows the air passages in your nose, which restricts airflow.