“Your doctor will conduct several tests to determine how your lungs function and monitor their progress,” Dr. Victoria Glass, MD, a practicing physician with the Farr Institute, tells Parade. “Some of these tests will lead to a diagnosis while others will inform your doctor if allergies are triggering your symptoms and/or condition.” “Doctors diagnose asthma through a series of tests, including lung function tests,” Sean Marchese, RN, a registered nurse at The Mesothelioma Center—adds. “Physical exams are also conducted and medical information is gathered.” Here’s everything you need to know about how asthma is diagnosed, and how you can advocate for yourself if you feel you’re not being heard.

How is asthma diagnosed?

Medical history

The first step to diagnosing asthma is talking to your doctor about your symptoms and medical history. Bring notes, if you have any—as these can help your doctor identify causes and/or triggers. Be prepared to answer questions about your symptoms. Giving a detailed account of your experience[s] will help your doctor identify the problem quicker. “Shortness of breath, wheezing, coughing and tightness in your chest [for example] may show asthma,” an article by the Asthma and Allergy Foundation of America explains. You should also provide information about your medical history, including medications you take and any/all. “A history of allergies or eczema increases your chance of asthma,” AAFA notes. “ A family history of asthma, allergies or eczema increases your chance of having asthma, too.”

Physical exam

If your doctor suspects you have asthma, they will conduct a thorough physical exam. “[Your doctor] will look at your ears, eyes, nose, throat, skin, chest and lungs,” AAFA explains. “This exam may include a lung function test to detect how well you exhale air from your lungs. You may also need an X-ray of your lungs or sinuses.” In short, you will get a routine workout—and then some.

Pulmonary function tests

To confirm asthma, your doctor may have you take one or more breathing tests known as lung function tests. These tests measure your breathing. “One medicine your doctor might use during these tests is a bronchodilator which can open up your airways. Then, your doctor will use spirometry to compare your breathing efficiency before and after the medication,” Marchese tells Parade. “Other tests they might use include exhaled nitric oxide measurements and challenge tests, which can determine if lung function drops during your respiratory spasms.” Common lung function tests used to diagnose asthma include:

Spirometry: Using a device called a spirometer this test measures the amount (and speed) of the air you blow out. Exhaled nitric oxide: Performed by having you breathe into a small, handheld machine, this test calculates the amount of nitric oxide you breathe out—a gaseous substance that is usually an indicator of inflammation.Challenge tests: Usually used as a last resort, challenge tests are implemented when other screening methods do not clearly or convincingly establish a diagnosis of asthma. “There are two types of challenge tests,” an article by the Cleveland Clinic explains. “Methacholine and mannitol. These agents when inhaled can cause the airways to spasm and narrow if asthma is present. During these tests, you will inhale increasing amounts of either methacholine aerosol mist or mannitol dry powder inhaler before and after lung function tests. The test is positive when your lung function drops during the challenge.”

It’s important to note that while these tests are valuable, they are not foolproof. Asthma, for example, can be exercise-induced. However, lung function tests may not pick up on this type and/or form. 

Additional tests

If your doctor suspects that you have a secondary condition in addition to asthma, you may need additional tests. These may include, but are not limited to:

X-rays or computerized tomography (CT) imaging of your chestCT scans of your sinusesBlood testsAllergy panelGastroesophageal reflux assessment

That said, even with proper testing, an asthma diagnosis can be missed. If you still believe you have asthma after speaking with your doctor and undergoing the aforementioned tests, you should seek a second opinion. You can also reach out to the Asthma and Allergy Foundation of America for support, as they can connect you with others in your local community and online. You can also call their free helpline for additional resources, information, and support.

Sources

Dr. Victoria Glass, MD, a practicing physicianSean Marchese, registered nurse Asthma Diagnosis. Asthma and Allergy Foundation of America.Asthma: Testing and Diagnosis. Cleveland Clinic How Is Asthma Diagnosed  Here s Everything You Need to KNow - 18