Asthavent Inhaler is a bronchodilator medicine that is used in the treatment or prevention of bronchospasm (narrowing of the airways) associated with chronic obstructive pulmonary disease (blockage of airflow to your lungs) and asthma (a condition that causes breathing difficulty). It works by relaxing and widening the blocked air passages of your lungs. Thus it improves the airflow to your lungs and makes breathing easier.