What is a Methacholine Challenge Test?
Methacholine Challenge Testing is a test used by your caregiver to determine if your child may have asthma.
Description of the Test
Your child will first perform a breathing test to determine their baseline lung function. During the test, your child will be asked to inhale, by a mist aerosol, doses of methacholine; a drug that may cause the airways to narrow. The test starts with a very small dose of methacholine. Doses will be gradually increased and a breathing test will be repeated after each dose to measure how much the airways narrow. The testing will be completed if your child either shows signs that the airways are narrowing on the breathing test or reaches the highest dose used in the test without airway narrowing.
Length of Test
The test may take up to 90 minutes.
Preparing Your Child for the Test
There is a list of medications that may decrease your child's response to the methacholine and should be avoided, only if possible, before testing. Check with your child's doctor before stopping any medication before this test, or call the PFT Laboratory at 513-636-8959.
Possible Side Effects of the Test
Thousands of methacholine challenge tests have been done with no serious side effects. In rare cases, methacholine may cause coughing, chest tightness, or shortness of breath; however, your child will be continuously monitored by the pulmonary function technologist for any side effects. If the test shows that there is airway narrowing, your child will be given an inhaled bronchodilator to relieve symptoms.
