Bronchial Provocation or Methacholine Challenge Test
A Bronchial Provocation or Methacholine challenge is a test to determine if you have asthma. These test for airway hyperreactivity are useful when baseline spirometry is normal or only slightly obstructed. Challenge testing is performed to measure the severity of bronchial reactivity (also called bronchial responsiveness, airway(s) reactivity, or bronchial hyper reactivity). The vast majority of normal individuals show no change in lung function when they inhale low concentrations of substances such as histamine or methacholine. On the other hand, nearly all individuals with active asthma exhibit narrowing of their airways when they inhale low concentrations of these substances.
How is test performed
You will be asked to perform a lung function test prior to receiving the challenge medication. The challenge medication will be given in aerosolized form (mist) which you will be asked to breathe in for a specified time.
- The test will continue until you reach at least a 20% drop in your FEV1 (the amount of air you exhale in the first second) or you finish all the dosages of the medication.
- After the testing is completed, you may be given a nebulizer treatment that will reverse the action of the methacholine, if it has caused your results to change.
- After each dose and after the breathing (nebulizer) treatment, you will be asked to perform several breathing tests.
- The testing time varies and may take up to 2 hours, depending on how you do.
You may have some mild shortness of breath from taking the medication. True asthma attacks are very rare and generally respond promptly to treatment.
How long will the test take
Bronchial provocation testing often takes 1 ½ to 2 hours.
Prior to coming in for testing, you may be asked not to take some of your morning medications:
The following medications need to be avoided 48 hours prior to testing.
- Oral bronchodilators--Slobid, Theodur, Uniphyll, Unidur, Theophylline
- Antihistamines--Claritin (regular and D), Allegra (regular and D), Benadryl, Bromfed, Atrohist, and over-the counter cold, cough and sinus medications.
- Inhaled – Advair, Serevent, Foradil
The following medications need to be avoided 24 hours prior to testing.
- Oral steroids--Prednisone, Medrol, Methylpredisolone
- Oral bronchodilators--Proventil Repetabs
- Oral Leukotrienes—Accolate, Zyflo, Singulair
The following medications need to be avoided 6-8 hours prior to testing:
- Bronchodilators--Albuterol, Ventoline, Proventil, Maxair, Brethaire, Atrovent, Combivent
Avoid all caffeine 6 hours prior to testing. NORMAL DIET - no fasting is necessary
Bronchial Provocation Testing is performed on the 6th floor of Rainbow Babies and Children’s Hospital in the Bryan Diagnostic Center . Our center is staffed by specially trained respiratory therapists and technicians.
If your doctor has requested that a Bronchial Provocation Test be performed on your child, you can call 216-844-TEST to set-up an appointment.