title: Effects of two antihistamines on chloroquine and histamine induced weal and flare in healthy African volunteers.
abstract: This study investigated the effects of single doses of clemastine (2mg orally), mepyramine (2 micrograms intradermally) and placebo on weal and flare caused by intradermal chloroquine 2.5mg and histamine 2 micrograms in 11 healthy black subjects who experienced generalised pruritus with oral chloroquine. Compared with placebo, both antihistamines caused significant reductions in histamine-induced weal and flare. By contrast, chloroquine-induced weal and flare were not significantly altered by clemastine or mepyramine when compared with placebo. It is concluded that histamine is unlikely to be the main mediator of chloroquine-induced weal and flare. These findings are in consonance with the lack of significant effect of antihistamines on chloroquine-induced generalised pruritus.
authors.affiliation: Department of Pharmacology, College of Health Sciences, University of Port Harcourt, Nigeria.
authors.forename: B
authors.initials: B
authors.lastname: Abila
authors.forename: I C
authors.initials: IC
authors.lastname: Ezeamuzie
authors.forename: P S
authors.initials: PS
authors.lastname: Igbigbi
authors.forename: A W
authors.initials: AW
authors.lastname: Ambakederemo
authors.forename: L
authors.initials: L
authors.lastname: Asomugha
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D044383:Black People; D002738:Chloroquine / Q000009:adverse effects*; D002974:Clemastine / Q000627:therapeutic use*; D018592:Cross-Over Studies; D006632:Histamine / Q000009:adverse effects* / Q000502:physiology; D006801:Humans; D007271:Injections, Intradermal; D008297:Male; D011537:Pruritus / Q000139:chemically induced / Q000188:drug therapy* / Q000503:physiopathology; D011738:Pyrilamine / Q000627:therapeutic use*; D016037:Single-Blind Method
chemical_list: D006632:Histamine; D002738:Chloroquine; D002974:Clemastine; D011738:Pyrilamine