Your primary care doctor will diagnose asthma based on your medical and family histories, a physical exam, and test results.
Your doctor also will figure out the severity of your asthma—that is, whether it's intermittent, mild, moderate, or severe. The level of severity will determine what treatment you'll start on.
You may need to see an asthma specialist if:
Your doctor may ask about your family history of asthma and allergies. He or she also may ask whether you have asthma symptoms and when and how often they occur.
Let your doctor know whether your symptoms seem to happen only during certain times of the year or in certain places, or if they get worse at night.
Your doctor also may want to know what factors seem to trigger your symptoms or worsen them. For more information about possible asthma triggers, go to "What Are the Signs and Symptoms of Asthma?"
Your doctor may ask you about related health conditions that can interfere with asthma management. These conditions include a runny nose, sinus infections, reflux disease, psychological stress, and sleep apnea.
Your doctor will listen to your breathing and look for signs of asthma or allergies. These signs include wheezing, a runny nose or swollen nasal passages, and allergic skin conditions (such as eczema).
Keep in mind that you can still have asthma even if you don't have these signs on the day that your doctor examines you.
Your doctor will use a test called spirometry (spi-ROM-eh-tre) to check how your lungs are working. This test measures how much air you can breathe in and out. It also measures how fast you can blow air out.
Your doctor also may give you medicine and then test you again to see whether the results have improved.
If the starting results are lower than normal and improve with the medicine, and if your medical history shows a pattern of asthma symptoms, your diagnosis will likely be asthma.
Your doctor may recommend other tests if he or she needs more information to make a diagnosis. Other tests may include:
Most children who have asthma develop their first symptoms before 5 years of age. However, asthma in young children (aged 0 to 5 years) can be hard to diagnose.
Sometimes it's hard to tell whether a child has asthma or another childhood condition. This is because the symptoms of asthma also occur with other conditions.
Also, many young children who wheeze when they get colds or respiratory infections don't go on to have asthma after they're 6 years old.
A child may wheeze because he or she has small airways that become even narrower during colds or respiratory infections. The airways grow as the child grows older, so wheezing no longer occurs when the child gets colds.
A young child who has frequent wheezing with colds or respiratory infections is more likely to have asthma if:
The most certain way to diagnose asthma is with a lung function test, a medical history, and a physical exam. However, it's hard to do lung function tests in children younger than 5 years. Thus, doctors must rely on children's medical histories, signs and symptoms, and physical exams to make a diagnosis.
Doctors also may use a 4–6 week trial of asthma medicines to see how well a child responds.
Living With and Managing Asthma
Clinical trials are research studies that explore whether a medical strategy, treatment, or device is safe and effective for humans. These studies are a key research tool for advancing medical knowledge and patient care. Learn more about clinical trials.
Clinical trials currently are under way for Asthma. For more information about these studies, visit www.clinicaltrials.gov.
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Because children are not little adults, they need clinical research that focuses exclusively on them. Clinical research will bring us closer to finding the best treatments, medicines, and devices for children who are growing and developing.
Visit the NHLBI’s Children and Clinical Studies Web site to hear experts, parents, and children talk about their experiences with clinical research.
The NHLBI updates Health Topics articles on a biennial cycle based on a thorough review of research findings and new literature. The articles also are updated as needed if important new research is published. The date on each Health Topics article reflects when the content was originally posted or last revised.