Early protective effects of tiotropium bromide in patients with airways hyperresponsiveness.
Tiotropium is an anticholinergic drug for Chronic Obstructive Pulmonary Disease (COPD) patients, with a peak bronchodilator effect observed after 1.5 to 2 hours and a long duration of action. The aim of our study was to quantify the early protection of a single dose of inhaled tiotropium against methacholine-induced bronchoconstriction in asthmatic patients with airway hyperresponsiveness. Ten subjects (7M, 3F), with history of asthma and a baseline FEV(1) (Forced Expiratory Volume 1 sec) > 80% of predicted, were enrolled in the study. Each subject performed three methacholine challenge tests, with a time of 72 hours between each challenge: Test A (methacholine challenge test), and successively, at random, Test B (methacholine 30 minutes after inhaled Tiotropium) and Test C (methacholine 30 minutes after inhaled Placebo). PD20 (Provocative Dose causing a 20% decrease in basal FEV(1) value) was reached to assess airways responsiveness. All the subjects showed in Test A and Test C a mild-moderate airway hyperresponsiveness. In Test B no PD20 was reached at the inhaled maximum dose of methacholine (1600 microg), FEV(1) before tiotropium was 88.6% +/- 4.4, beginning test FEV(1) 92.6% +/- 4.3, end test FEV(1) 85.7% +/- 4.6. Inhaled tiotropium bromide 18 microg has shown a protective effect against methacholine-induced bronchoconstriction in asthmatic patients, with mild-moderate airways hyperresponsiveness, already 30 minutes after its administration.
Terzano
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Department of Cardiovascular and Respiratory Sciences, Respiratory Diseases Unit, Fondazione E. Lorillard Spencer Cenci, University "La Sapienza", Rome, Italy.
Petroianni
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A
Ricci
A
A
D'Antoni
L
L
Allegra
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L
D000280:Administration, Inhalation; D000328:Adult; D001249:Asthma / Q000188:drug therapy / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000139:chemically induced / Q000188:drug therapy* / Q000517:prevention & control; D001985:Bronchial Provocation Tests; D016084:Bronchoconstriction / Q000187:drug effects; D001993:Bronchodilator Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D018680:Cholinergic Antagonists / Q000008:administration & dosage / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D008297:Male; D016210:Methacholine Chloride; D012602:Scopolamine Derivatives / Q000008:administration & dosage / Q000627:therapeutic use*; D000069447:Tiotropium Bromide
D001993:Bronchodilator Agents; D018680:Cholinergic Antagonists; D012602:Scopolamine Derivatives; D016210:Methacholine Chloride; D000069447:Tiotropium Bromide