The protective effects of ipratropium bromide and terbutaline on distilled water-induced bronchoconstriction.
In a randomized, double-blind, placebo-controlled study, we investigated the protective effects of ipratropium bromide 160 micrograms and 320 micrograms and terbutaline 500 micrograms on ultrasonically nebulized distilled water (UNDW)-induced bronchoconstriction in nine stable asthmatic patients. Both drugs caused a significant increase (P < 0.001) in baseline FEV1 with no significant differences between the drugs or both doses of ipratropium bromide. Pre-inhalation of ipratropium bromide 320 micrograms and terbutaline 500 micrograms inhibited UNDW-induced bronchoconstriction (P < 0.01), whereas ipratropium bromide 160 micrograms had no protective effect. The protective effects of ipratropium bromide showed a large interindividual variation. There was no correlation between the increase in baseline FEV1 and PD20 UNDW, indicating that the protective effect on UNDW-induced bronchoconstriction is not dependent on the bronchodilation induced by terbutaline and ipratropium bromide. It also appears that the UNDW-induced bronchoconstriction is at least partly vagally mediated.
Groot
C A
CA
Department of Pulmonology, Leyenburg Hospital, The Hague, The Netherlands.
Lammers
J W
JW
Festen
J
J
van Herwaarden
C L
CL
D000280:Administration, Inhalation; D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000139:chemically induced / Q000517:prevention & control*; D016084:Bronchoconstriction / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D009241:Ipratropium / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D013726:Terbutaline / Q000627:therapeutic use*; D014867:Water / Q000008:administration & dosage*
D014867:Water; D009241:Ipratropium; D013726:Terbutaline