Sodium cromoglycate-induced changes in the dose-response curve of inhaled methacholine and histamine in asthmatic children.

The effect of inhalation of 2 per cent solution of sodium cromoglycate compared to that of saline on the bronchial response to methacholine and histamine was studied in 30 asthmatic children. Seven of 17 children challenged with methacholine showed decreased sensitivity after pretreatment with sodium cromoglycate. In 4 of 13 children, sodium cromoglycate attenuated the response to inhaled histamine. We conclude that in some asthmatic children, sodium cromoglycate provides significant protection against these nonallergenic challenges. This may have some therapeutic implications in the management of these patients. Our findings raise the possibility that sodium cromoglycate might have an action on cholinergic or irritant receptor sites in addition to inhibition of mast cell degranulation.