title: Comparison of the suppressive effect of astemizole, terfenadine, and hydroxyzine on histamine-induced wheals and flares in humans.
abstract: Thirty-two healthy volunteers completed a 14-day, double-blind, noncrossover study comparing the efficacy and adverse effects of astemizole, terfenadine, and hydroxyzine. The subjects received either astemizole (load), 30 mg once daily for 1 week and then 10 mg once daily for 1 week, or astemizole (no load), 10 mg once daily for 2 weeks, or terfenadine, 60 mg twice daily for 2 weeks, or hydroxyzine, 50 mg once daily for 2 weeks. Before and on days 7 and 14 of treatment, five intradermal tests with various amounts of histamine phosphate (range 0.3 to 40 micrograms) were performed. Wheal-and-flare responses were traced, and the areas were computed by use of a graphics tablet. All four H1-receptor antagonist treatment regimens were equally effective in reducing the flare response to histamine. Astemizole (load) and hydroxyzine were significantly more effective than terfenadine and astemizole (no load) in reducing wheal size. The incidence of adverse effects, including sedation, was low overall and lowest in the astemizole (no load) and terfenadine groups, although this difference was not statistically significant.
authors.forename: L
authors.initials: L
authors.lastname: Gendreau-Reid
authors.forename: K J
authors.initials: KJ
authors.lastname: Simons
authors.forename: F E
authors.initials: FE
authors.lastname: Simons
mesh_terms: D000328:Adult; D016589:Astemizole; D001559:Benzhydryl Compounds / Q000494:pharmacology*; D001562:Benzimidazoles / Q000494:pharmacology*; D004306:Dose-Response Relationship, Immunologic; D004311:Double-Blind Method; D005260:Female; D006632:Histamine / Q000494:pharmacology; D006801:Humans; D006919:Hydroxyzine / Q000494:pharmacology*; D006969:Hypersensitivity, Immediate / Q000139:chemically induced / Q000188:drug therapy*; D007166:Immunosuppressive Agents; D008297:Male; D012882:Skin Tests; D016593:Terfenadine
chemical_list: D001559:Benzhydryl Compounds; D001562:Benzimidazoles; D007166:Immunosuppressive Agents; D006919:Hydroxyzine; D016593:Terfenadine; D016589:Astemizole; D006632:Histamine