Bronchitis is inflammation of the bronchi.
In normal breathing, air travels through the nose and windpipe into narrowing airways called the bronchi. The bronchi branch into bronchioles and eventually into small clusters of thin, delicate sacs, the alveoli (medical name: alveoli).
Bronchitis is inflammation of the bronchi. When the tissue cells of the lining of the bronchi become excessively irritated, the tiny cilia (cilia) that normally trap and clear away pollutants stop working. In response to this, mucus production increases, and this mucus causes the characteristic bronchitis cough. The inflammation can be caused by viruses, bacteria, smoking or inhaling contaminating chemicals or dust.
