Spirometry is one of the many tests through which asthma can be diagnosed. Spirometry can also detect obstructive pulmonary disease (COPD) and a few other diseases that hamper the breathing process. In addition, it can also check the condition of the lungs in patients suffering from other chronic lung diseases (such as emphysema, pulmonary fibrosis and chronic bronchitis).

In a spirometry test, the amount of air that a patient breathes in (inhales) and the amount that the patient breathes out (exhales) are measured. It also measures the rate of breathing out (exhalation). If all these values are below than average, it indicates that the lungs are not functioning well, which in turn signifies lung conditions like asthma and COPD.

Asthma is a disease characterized by the inflammation of the bronchial tubes, or airways, of the lungs. The inflammation narrows down the airways. This obstructs the flow of air through the body. That’s why lower than expected values of the amount of flow of air and of the rate of breathing indicate asthma.

People who have already been diagnosed with asthma can take spirometry tests to find the effectiveness of their asthma medications in keeping asthma symptoms, such as coughing, wheezing, chest tightness and shortness of breath, under control.