Diagnosis - Asthma - Diagnosis

Your doctor may diagnose asthma based on your medical history, a physical exam, and results from diagnostic tests. Your history of asthma symptoms will help your doctor determine if you have mild, moderate, or severe asthma. The level of severity is used to determine the treatment you will receive.

Before diagnosing you with asthma, your doctor will rule out other medical reasons or conditions that could also cause similar signs and symptoms. You may need to see an asthma specialist, called a pulmonologist, or an allergy specialist, called an allergist.

Medical history
- Asthma - Diagnosis

Your doctor may ask about any known allergies and the pattern of your symptoms. This includes how often symptoms occur, what seems to trigger your symptoms, when or where symptoms occur, and if your symptoms wake you up at night.

Physical exam
- Asthma - Diagnosis

During the physical exam, your doctor may:

  • Listen to your breathing and look for signs of asthma such as wheezing, a runny nose, or swollen nasal passages
  • Look for allergic skin conditions, such as eczema

Diagnostic tests
- Asthma - Diagnosis

Several tests may be done to help determine if asthma is likely to be the cause of symptoms. These tests include:

  • Pulmonary function tests such as spirometry, which involves breathing in and out through a tube connected to a computer. This measures how much and how fast the air moves when you breathe in and out with maximum effort.
  • Spirometry with bronchodilator (BD) test to measure how much and how fast air moves in and out both before and after you take an inhaled medicine to relax the muscles in your airway.
  • Bronchoprovocation tests to measure how your airways react to specific exposures. During this test, you inhale different concentrations of allergens or medicines that may tighten the muscles in your airways. Spirometry can also be done before and after the test.
  • Peak expiratory flow (PEF) to measure how fast you can blow air out using maximum effort. This test can be done during spirometry or by breathing into a separate device, such as a tube.

Diagnosing asthma in children under age 6
- Asthma - Diagnosis

It can be hard to tell whether a child under 6 years old has asthma or another respiratory condition because they cannot perform a pulmonary function test such as spirometry. After checking a child’s history and symptoms, the doctor may try asthma medicines for a few months to see how well a child responds. About 40 percent of children who wheeze when they get colds or respiratory infections are eventually diagnosed with asthma.

Allergy tests
- Asthma - Diagnosis

If you have a history of allergies, your doctor may test to find out which allergens in the environment, such as pet dander or pollen, affect you. This can be a skin test or a blood test.

Tests for other medical conditions
- Asthma - Diagnosis

Your doctor may want to test for other conditions if your symptoms include:

  • A cough without other breathing issues
  • Chest pain
  • Coughing up mucus often
  • Difficult and noisy breathing during exercise
  • Shortness of breath with dizziness, light-headedness, or tingling in your hands or feet

Tests your doctor may use to rule out other medical conditions include:

  • Chest X-ray to rule out lung infections, such as tuberculosis, or a foreign substance, such as an object that was inhaled by accident.
  • Electrocardiogram (EKG) to rule out heart failure or arrhythmia while in emergency care.
  • Laryngoscopy to rule out vocal cord problems. The doctor can use this test to look at your upper airways and the vocal cords.
  • Sleep studies to rule out sleep apnea.
  • Tests that look at your esophagus and upper digestive system to rule out gastroesophageal reflux disease (GERD). These tests may include endoscopy, in which a small camera is placed in the esophagus, or an X-ray of the digestive system. Tests may also measure the acid in your esophagus or measure how food or other substances move through the esophagus. Some people have both GERD and asthma.

- Asthma - Diagnosis