[Ketotifene: experimental and clinical data].

Some important pharmacodynamic and clinical data on ketotifen, a benzocycloheptathiophene used in the prophylaxis of allergic asthma, are provided as an introduction to papers discussing the therapeutic use of this substance in adults and children. Ketotifen, which is active when administered orally, has a therapeutic efficacy comparable to that of cromoglycate but characterized by a somewhat different mechanism of action. The therapeutic efficacy of ketotifen appears to be associated with a progressive diminution of bronchial hyper-reactivity to various specific or nonspecific spasmogenic factors (allergens, histamine, exercise). An antagonistic action to, and an inhibitory effect on, the activation and release of the principal mediators of anaphylactic hypersensibility (SRS-A, histamine) have been demonstrated in several experimental models both in animals and in man.