Influence of drug therapy on bronchial hyperreactivity.

Bronchial hyperreactivity was confirmed in eleven nonselected patients with chronic respiratory disease during a period of quiescence by inhalative provocation with histamine. After one week's treatment with ketotifen a protective effect against the histamine-induced bronchospasm was observed in nine patients. The rapid appearance of this protective mechanism was demonstrated both in patients with exogenous and endogenous bronchial asthma and in the three patients with chronic bronchitis. Regardless of the fact that specific bronchospasmolysis is the main therapeutic measure, based on our experience the protective mechanism of mast-cell stabilizers as supplementary therapy is at present at an earlier point of time than is generally assumed.