This test is used to find out how well your lungs are working.

This test is done with a spirometer and a bronchodilator. A spirometer is a machine that measures lung function. It measures how much and how fast air is blown out or exhaled. Bronchodilators are medicines that open the airways. This makes it easier to breathe.

This test is often used in people who have asthma or chronic obstructive pulmonary disease (COPD). It may be done to help diagnose either condition. The test is done to see if the person has any improvement in airflow after taking the bronchodilator medicine.

You may be told not to take your normal bronchodilator medicine before the test. Make sure you follow the instructions exactly as given. Be certain to ask questions if the pretest instructions are not clear.

This test is often done in your doctor's office. The testing often goes like this:

1. You will be asked to take a deep breath. Then you will blow into the spirometer as hard as you can. The spirometer records the results. This is called a baseline measurement. You will be asked to do this a few times in a row to get the best results.

2. You will be given a dose of bronchodilator medicine. To do this, you will use an inhaler or nebulizer.

3. You will wait for about 15 minutes.

4. You will take a deep breath. Then you will blow into the spirometer as hard as you can. Again, it will record the results.

5. You will be asked to blow into the spirometer more than once. This is done to get the best reading you can.

Your doctor will make, confirm, or exclude a diagnosis of lung disease after this test. Your doctor will also use information from:

• Your health history
• Results of a physical exam
• The results of other tests

The results of this test may be used to check your lung condition. It can help your doctor choose the best treatment for you.