Production of IgE complexes by allergen challenge in atopic patients and the effect of sodium cromoglycate.

Specific IgE complexes and symptoms of asthma and eczema were produced in two allergic patients by oral challenge with food allergen. Both symptoms and IgE complexes could be prevented by pre-treatment with oral sodium cromoglycate. The IgE complexes can fix complement and may therefore provide the vehicle of the "late" responses seen in immediate hypersensitivity. The central role of gut sensitivity is emphasised by the protection afforded by sodium cromoglycate both when given acutely, against the effects of an oral challenge, and when given continuously for asthma and eczema due to food allergy.