Allergen-induced increase in non-allergic bronchial reactivity

Clin Allergy. 1977 Nov;7(6):503-13. doi: 10.1111/j.1365-2222.1977.tb01481.x.


Non-allergic bronchial hyper-reactivity is a feature of most patients with asthma. We have measured non-allergic bronchial reactivity to inhaled histamine and methacholine in thirteen asthmatic subjects before and after allergen inhalation in the laboratory. The allergen inhalation produced mild early asthmatic responses (19-40% FEV1 fall) in all thirteen, additional definite late asthmatic responses (17-29% FEV1 fall) in four, and equivocal late asthmatic responses (5-11% FEV1 fall) in five. Following allergen inhalation, non-allergic bronchial reactivity increased in seven for up to 7 days. The seven included all four with definite late asthmatic responses and three of the five with equivocal late asthmatic responses. We conclude that allergens make asthma worse, partly through non-allergic mechanisms, and that avoidance of allergens is important in reducing non-allergic bronchial hyper-reactivity.

MeSH terms

  • Allergens*
  • Asthma / complications
  • Asthma / diagnosis
  • Asthma / etiology*
  • Forced Expiratory Volume
  • Histamine
  • Humans
  • Methacholine Compounds
  • Time Factors


  • Allergens
  • Methacholine Compounds
  • Histamine