Nasal congestion, aka sinus congestion, stuffy nose, runny nose or blocked nose, occurs when there is irritation or inflammation of the nasal cavities which leads to accumulation of mucus. Due, to the accumulation of mucus, you find it difficult to breathe well. Nasal congestion often accompanies flu, catarrh, allergic reactions, common cold, sinus infection, etc. Nasal congestions could also be caused by tumors or nasal polyps. Nasal congestion usually subsides within 7 days. However, when t...