Bronchodilator reversibility testing consists of performing baseline spirometry measurements followed by administration of a bronchodilator inhaler and repeating spirometry again. The initial results are compared to the post results after taking a bronchodilator medication.

If there is a significant improvement in lung function after using the bronchodilator, it suggests bronchial responsiveness, commonly linked to conditions like asthma. This test is essential in the diagnosis of fixed and reversible airway obstructions that are indicative of asthma and COPD.

You can learn more about Asthma and COPD here