agents triggering airway hyperactivity

Last reviewed 04/2020

In response to a number of stimuli and in the apparent absence of an allergic IgE mediated response, individuals with asthma may experience bronchoconstriction and airflow limitation in response to stimuli such as:

  • upper respiratory tract infection
    • predominantly viral
    • more common in children than in adults and during winter than in summer
  • smoking
  • occupational sensitisers - for example
    • colophony fumes in the soldering and the electronics industry
    • chemicals - isocyanates in industrial coatings, platinum salts, aluminium (1)
  • psychological factors such as stress and emotion
  • exercise
  • cold air and exercise
  • drugs - such as beta blockers, aspirin and NSAIDs, angiotensin-converting enzyme inhibitors (ACEI’s) (1)
    • ACEIs - symptoms of airway obstruction in relation to treatment with angiotensin converting enzyme inhibitors seem to be a rare but potentially serious reaction generally occurring within the first few weeks of treatment (2)

Variation in symptoms throughout the working week may provide a clue to an occupational allergen. A seasonal pattern implies seasonal allergen exposure.