Hospital tests

11) The Histamine/Methacholine Challenge Test

Female patient using a nebuliser


During the Histamine/Methacoline test:

  • You will have resting Spirometry taken before starting the challenge test.
  • You will be asked to breathe in a small amount of the irritant for 2 minutes through a nebuliser.
  • You will have Spirometry repeated within 90 seconds after the nebuliser stops.
  • This is then repeated, gradually increasing the strength of histamine/methacoline to check how your airways react to this irritant.
  • This continues until maximum strength has been used or a reaction happens.

This test will show how reactive the airways are to irritant that may be causing your symptoms.

  • At this point, a nebuliser of reliever will be given to you to relieve any symptoms and relax your airways so that your breathing will return to normal resting levels.

You will be closely supervised by a physiologist during and after this test.