title: Effects of bepotastine and fexofenadine on histamine-induced flare, wheal and itch.
abstract: BACKGROUND
  Urticaria is mainly caused by mast cell-derived histamine through the histamine H(1) receptor. Antihistamines are occasionally used on demand upon a recurrence of urticaria; therefore, rapidly acting agents should be explored. The onset of action is assumed to depend on time to maximum concentration (T(max)), but the speed of action needs to be evaluated not only through blood concentration analysis but also by measuring in vivo effectiveness.
  
  
  METHODS
  In this study, we chose two representative second-generation antihistamines (bepotastine and fexofenadine) with relatively short T(max) values and evaluated their effects on histamine-induced skin responses using both visual and laser Doppler imaging scales.
  
  
  RESULTS
  Suppression of histamine-induced flare and itch was observed 3 and 6 h after administration of both antihistamines. Attenuation of itch was seen 30 min after the administration of each drug and thereafter until 6 h. In addition, bepotastine suppressed flare formation after only 30 min following application.
  
  
  CONCLUSIONS
  These results suggest that antihistamines suppress histamine-induced itch and flare, followed by wheal formation, and that bepotastine suppresses skin symptoms sooner after administration than fexofenadine does, which is relatively consistent with the T(max) results.
authors.affiliation: Department of Dermatology, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Tanizaki
authors.forename: Akihiko
authors.initials: A
authors.lastname: Ikoma
authors.forename: Miyuki
authors.initials: M
authors.lastname: Fukuoka
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Miyachi
authors.forename: Kenji
authors.initials: K
authors.lastname: Kabashima
mesh_terms: D000328:Adult; D005260:Female; D006632:Histamine / Q000009:adverse effects; D039563:Histamine H1 Antagonists, Non-Sedating / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D008297:Male; D010880:Piperidines / Q000494:pharmacology / Q000627:therapeutic use*; D011537:Pruritus / Q000188:drug therapy*; D011725:Pyridines / Q000494:pharmacology / Q000627:therapeutic use*; D012867:Skin / Q000187:drug effects / Q000473:pathology; D016593:Terfenadine / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D014581:Urticaria / Q000188:drug therapy*
chemical_list: D039563:Histamine H1 Antagonists, Non-Sedating; D010880:Piperidines; D011725:Pyridines; C511534:bepotastine besilate; D016593:Terfenadine; D006632:Histamine; C093230:fexofenadine