Asthma results from inflammation of the tubes that connect the windpipe to the lungs, known as bronchi. Swelling causes the airway passages to contract. It also increases the production of phlegm, which obstructs the airways further. This leads to symptoms including coughing, wheezing and tightness of the chest and trouble breathing. Ventolin blue inhaler works by opening up the airways to increase airflow and oxygen to the lungs. This process offers to relieve asthma symptoms within a short duration. It is an excellent reliever for asthma. Ventolin works pre-emptively before you exercise or encounter an allergen.