title: Cimetidine's effect on dermal H1-receptor antagonist tolerance.
abstract: The effect of the H2-receptor antagonist cimetidine upon H1-receptor antagonist tolerant histamine induced weal and flare responses was studied in nine healthy male subjects taking clemastine 1 mg orally twice a day. After 21 days clemastine therapy, the weal response became tolerant to clemastine but the flare response did not. Cimetidine, 400 mg, did not produce a significantly greater decrease in the area of the H1-receptor antagonist tolerant weal response than in the non-tolerant weal response. The results suggest that histamine mediated skin reactions may develop a tolerance to H1-receptor antagonist therapy that cannot be overcome by the addition of the H2-receptor antagonist cimetidine.
authors.forename: G M
authors.initials: GM
authors.lastname: Fairris
authors.forename: N
authors.initials: N
authors.lastname: Fairris
mesh_terms: D000328:Adult; D002927:Cimetidine / Q000494:pharmacology*; D002974:Clemastine / Q000494:pharmacology; D002986:Clinical Trials as Topic; D004311:Double-Blind Method; D006632:Histamine / Q000276:immunology; D006634:Histamine H1 Antagonists / Q000276:immunology*; D006801:Humans; D007108:Immune Tolerance / Q000187:drug effects*; D008297:Male; D011897:Random Allocation; D012867:Skin / Q000276:immunology*
chemical_list: D006634:Histamine H1 Antagonists; D002927:Cimetidine; D006632:Histamine; D002974:Clemastine