The Inhibiting Effect of Cetirizine 2 HCl on Eosinophil Migration and Its Link to H1 Blockade

Since the demonstration of an inhibiting effect of cetirizine on an antigen induced eosinophils' migration in the skin of atopic subjects, a series of in vitro and in vivo studies were performed in order to clarify the mechanism of action of this new H1-blocker. The studies used FMLP and PAF as agonists, and BN 52021, dexchlorpheniramine, terfenadine and loratadine as reference compounds. The results suggest that the inhibiting effect of cetirizine on the eosinophils' migration is independent of its specific H1 blocking activity.