Modern histamine H1-receptor antagonists in the unified airway

To the Editor:Deruaz and colleagues1.Deruaz C. Leimgruber A. Berney M. Pradervand E. Spertini F. Levocetirizine better protects than desloratadine in a nasal provocation with allergen.J Allergy Clin Immunol. 2004; 113: 669-676Abstract Full Text Full Text PDF PubMed Scopus (47) Google Scholar examined the relative efficacies of desloratadine and levocetirizine in attenuating the response to nasal provocation with grass pollen in sensitized individuals. However, the findings of the study are surprising in light of recent published data with regard to the relative effects of modern histamine H1-receptor antagonists in the unified airway.2.Lee D.K. Gardiner M. Haggart K. Fujihara S. Lipworth B.J. Comparative effects of desloratadine, fexofenadine, and levocetirizine on nasal adenosine monophosphate challenge in patients with perennial allergic rhinitis.Clin Exp Allergy. 2004; 34: 650-653Crossref PubMed Scopus (49) Google Scholar, 3.Lee D.K. Bates C.E. Currie G.P. Lipworth B.J. Comparative in vivo bioactivity of modern H1-antihistamines on AMP challenge in atopic asthma.J Allergy Clin Immunol. 2003; 111: 337-341Abstract Full Text Full Text PDF PubMed Scopus (25) Google ScholarNasal congestion, as measured by peak nasal inspiratory flow and acoustic rhinometry, was unaffected by desloratadine and levocetirizine compared with placebo. The lack of difference between the histamine H1-receptor antagonists is not surprising; however, the finding of no detectable difference from placebo was unexpected. There are 2 possible explanations for this apparent lack of effect compared with placebo. First, peak nasal inspiratory flow and the minimal cross-sectional area were measured after nasal lavage, and this may have increased the threshold for detecting any discernible changes in nasal congestion after treatment with desloratadine and levocetirizine. Second, nasal provocation with an allergen such as grass pollen may be less sensitive in detecting responses to histamine H1-receptor antagonists compared with other provocative agents, such as adenosine monophosphate. Adenosine monophosphate has been shown to correlate well with airway inflammation.4.van den Berge M. Kerstjens H.A. Postma D.S. Provocation with adenosine 5′-monophosphate as a marker of inflammation in asthma, allergic rhinitis and chronic obstructive pulmonary disease.Clin Exp Allergy. 2002; 32: 824-830Crossref PubMed Scopus (33) Google ScholarFurther studies are now required to evaluate the relative long-term effects of modern histamine H1-receptor antagonists in the unified airway and to assess their effects on nasal and bronchial inflammatory cells. To the Editor: Deruaz and colleagues1.Deruaz C. Leimgruber A. Berney M. Pradervand E. Spertini F. Levocetirizine better protects than desloratadine in a nasal provocation with allergen.J Allergy Clin Immunol. 2004; 113: 669-676Abstract Full Text Full Text PDF PubMed Scopus (47) Google Scholar examined the relative efficacies of desloratadine and levocetirizine in attenuating the response to nasal provocation with grass pollen in sensitized individuals. However, the findings of the study are surprising in light of recent published data with regard to the relative effects of modern histamine H1-receptor antagonists in the unified airway.2.Lee D.K. Gardiner M. Haggart K. Fujihara S. Lipworth B.J. Comparative effects of desloratadine, fexofenadine, and levocetirizine on nasal adenosine monophosphate challenge in patients with perennial allergic rhinitis.Clin Exp Allergy. 2004; 34: 650-653Crossref PubMed Scopus (49) Google Scholar, 3.Lee D.K. Bates C.E. Currie G.P. Lipworth B.J. Comparative in vivo bioactivity of modern H1-antihistamines on AMP challenge in atopic asthma.J Allergy Clin Immunol. 2003; 111: 337-341Abstract Full Text Full Text PDF PubMed Scopus (25) Google Scholar Nasal congestion, as measured by peak nasal inspiratory flow and acoustic rhinometry, was unaffected by desloratadine and levocetirizine compared with placebo. The lack of difference between the histamine H1-receptor antagonists is not surprising; however, the finding of no detectable difference from placebo was unexpected. There are 2 possible explanations for this apparent lack of effect compared with placebo. First, peak nasal inspiratory flow and the minimal cross-sectional area were measured after nasal lavage, and this may have increased the threshold for detecting any discernible changes in nasal congestion after treatment with desloratadine and levocetirizine. Second, nasal provocation with an allergen such as grass pollen may be less sensitive in detecting responses to histamine H1-receptor antagonists compared with other provocative agents, such as adenosine monophosphate. Adenosine monophosphate has been shown to correlate well with airway inflammation.4.van den Berge M. Kerstjens H.A. Postma D.S. Provocation with adenosine 5′-monophosphate as a marker of inflammation in asthma, allergic rhinitis and chronic obstructive pulmonary disease.Clin Exp Allergy. 2002; 32: 824-830Crossref PubMed Scopus (33) Google Scholar Further studies are now required to evaluate the relative long-term effects of modern histamine H1-receptor antagonists in the unified airway and to assess their effects on nasal and bronchial inflammatory cells. ReplyJournal of Allergy and Clinical ImmunologyVol. 114Issue 3Preview Full-Text PDF