Effect of astemizole on antigen-mediated histamine release from the blood of patients with allergic rhinitis

The main objective of this study was to test the effectiveness of astemizole in vitro in blocking the release of histamine from blood of patients with allergic rhinitis. The results of this investigation indicated that astemizole inhibited allergen-mediated histamine release from blood basophils of patients with this allergic disorder. The inhibition by astemizole (33-156 mumol) was immediate, requiring no pre-incubation of the cells, and was dose-dependent, with maximal inhibition of about 91%. The relatively high potency of astemizole in inhibiting the immunologic release of histamine may provide an additional measure in the treatment of allergic rhinitis with this H1-receptor antagonist.