17523
document
Single and short-term dosing effects of levocetirizine on adenosine monophosphate bronchoprovocation in atopic asthma . AIMS Adenosine monophosphate ( AMP ) acts indirectly via primed airway mast cells to induce bronchial hyper-responsiveness , which in turn correlates with eosinophilic asthmatic inflammation and atopic disease expression . We evaluated single and short-term dosing effects of a modern histamine H1-receptor antagonist , levocetirizine , given at the usual clinically recommended dose , on the primary outcome of AMP bronchoprovocation . METHODS Fifteen atopic asthmatics were randomized in double-blind , cross-over fashion to receive for 1 week either levocetirizine 5 mg or placebo . There was a 1-week washout period prior to each randomized treatment . The provocative concentration of AMP producing a 20 % fall in FEV1 ( PC20 ) was measured after each washout at baseline and at 4-6 h following the first and last doses of each randomized treatment . RESULTS Baseline mean +/- SEM values after washout prior to each randomized treatment comparing levocetirizine vs placebo were not significantly different for prechallenge FEV1 ( % predicted ) 83 +/- 4 vs 82 +/- 4 , or AMP PC20 ( mg ml ( -1 ) ) 45 +/- 24 vs 45 +/- 22 , respectively . Airway calibre as prechallenge FEV1 for levocetirizine vs placebo was not significantly different following the first dose 86 +/- 4 vs 82 +/- 4 , or the last dose 85 +/- 4 vs 83 +/- 4 , respectively . There were significant improvements ( P < 0.05 ) in AMP PC20 comparing levocetirizine vs placebo following the first dose 123 +/- 73 vs 48 +/- 24 , a 1.4 doubling dilution difference ( 95 % CI 0.8 , 1.9 ) , and the last dose 127 +/- 74 vs 53 +/- 29 , a 1.2 doubling dilution difference ( 95 % CI 0.5 , 2.0 ) . AMP PC20 was also improved ( P < 0.05 ) by the first and last doses of levocetirizine but not placebo , vs respective baseline values , with there being no difference in the degree of protection between first and last doses . CONCLUSIONS Single and short-term dosing with levocetirizine conferred similar improvements in bronchial hyper-responsiveness to AMP challenge , which was unrelated to prechallenge airway calibre . Further studies are indicated to evaluate the longer-term effects of levocetirizine on asthma exacerbations .
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Intervention_Pharmacological
levocetirizine
17525
Intervention_Pharmacological
levocetirizine
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Intervention_Pharmacological
levocetirizine 5 mg
17527
Intervention_Control
placebo
17528
Intervention_Pharmacological
levocetirizine
17529
Intervention_Control
placebo
17530
Intervention_Pharmacological
levocetirizine
17531
Intervention_Control
placebo
17532
Intervention_Pharmacological
levocetirizine
17533
Intervention_Pharmacological
levocetirizine
17534
Outcome_Physical
eosinophilic asthmatic inflammation
17535
Outcome_Physical
atopic disease expression
17536
Outcome_Physical
mean +/- SEM values
17537
Outcome_Physical
FEV1
17538
Outcome_Physical
AMP PC20
17539
Outcome_Physical
Airway calibre as prechallenge FEV1
17540
Outcome_Physical
AMP PC20
17541
Outcome_Physical
AMP PC20
17542
Outcome_Physical
bronchial hyper-responsiveness to AMP
17543
Outcome_Physical
asthma exacerbations
17544
Participant_Sample-size
Fifteen
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Participant_Condition
atopic asthmatics