Effects of H1-receptor blockade with terfenadine in nocturnal asthma.
1. In a single-blind placebo controlled study we have measured peak flow (PEFR) at 04.00 h and 16.00 h in eight asthmatics 6 h after placebo or terfenadine 120 mg, to determine if diurnal variation in histamine mediated effects contribute to nocturnal bronchoconstriction in asthma. 2. On placebo there was a significant diurnal variation in mean PEFR of 41 l min-1 (P less than 0.05). Terfenadine improved 04.00 h baseline mean PEFR from 242 to 278 l min-1 (P less than 0.05) but a 38 l min-1 diurnal variation in mean PEFR persisted (P less than 0.05). 3. We conclude that H1-receptor blockade with terfenadine may produce modest nocturnal bronchodilatation but does not influence the diurnal variation in PEFR in asthma suggesting that H1-receptor mediated effects are not important in the pathogenesis of nocturnal asthma.
Teale
C
C
Pulmonary Function Laboratory, Killingbeck Hospital, Leeds.
Morrison
J F
JF
Pearson
S B
SB
D000328:Adult; D000368:Aged; D001249:Asthma / Q000188:drug therapy*; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010919:Placebos; D011968:Receptors, Histamine / Q000187:drug effects*; D016593:Terfenadine / Q000494:pharmacology* / Q000627:therapeutic use
D010919:Placebos; D011968:Receptors, Histamine; D016593:Terfenadine