Effects of fexofenadine on the early response to nasal allergen challenge.

Abstract

BACKGROUND:

Previous studies using nasal allergen challenge models have shown that terfenadine, an H1 antihistamine, inhibits histamine release during the early response to allergen provocation. Fexofenadine, the active metabolite of terfenadine, has strong H1-antihistaminic activity and no cardiac effects. Clinical studies have documented the efficacy of fexofenadine in the treatment of allergic rhinitis.

OBJECTIVE:

To determine whether fexofenadine, like terfenadine, inhibits histamine and tryptase release during the early allergic response.

METHODS:

Randomized, double blind, placebo-controlled, two-way crossover study in 20 subjects with seasonal allergic rhinitis, out of their allergy season (median age 27.5 years, 13 males and 7 females). Subjects were medicated with either placebo or fexofenadine 180 mg orally daily for 1 week followed by nasal challenge with allergen. After each challenge, sneezes and nasal symptoms were recorded, and a nasal lavage was obtained for the assay of albumin, an indicator of vascular permeability, and histamine and tryptase, indicators of mast cell degranulation.

RESULTS:

When patients were on placebo, allergen challenges led to significant increases in all measured parameters compared with the sham challenges with diluent. Treatment with fexofenadine resulted in inhibition of allergen-induced symptoms and increased vascular permeability, but not the release of histamine and tryptase.

CONCLUSION:

Fexofenadine is an effective H1 antihistamine, but in contrast to its parent compound, terfenadine, it does not affect the release of the mast cell mediators histamine and tryptase.

• Authors: Frances T Allocco, Virginia Votypka, Marcy deTineo, Robert M Naclerio, Fuad M Baroody
• Journal: Annals of allergy, asthma & immunology : official publication of the American College of Allergy, Asthma, & Immunology (Ann Allergy Asthma Immunol) Vol. 89 Issue 6 Pg. 578-84 (Dec 2002) ISSN: 1081-1206 [Print] United States
• PMID: 12487223 (Publication Type: Clinical Trial, Comparative Study, Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Allergens
• Biomarkers
• Histamine H1 Antagonists
• Serum Albumin
• Terfenadine
• fexofenadine
• Serine Endopeptidases
• Tryptases

Topics

• Adolescent
• Adult
• Allergens
• Biomarkers
• Capillary Permeability (drug effects)
• Cross-Over Studies
• Double-Blind Method
• Female
• Histamine H1 Antagonists (chemistry, pharmacology)
• Histamine Release (drug effects)
• Humans
• Male
• Mast Cells (drug effects, metabolism)
• Middle Aged
• Molecular Structure
• Nasal Cavity
• Nasal Provocation Tests
• Pruritus (etiology)
• Rhinitis, Allergic, Seasonal (drug therapy)
• Serine Endopeptidases (metabolism)
• Serum Albumin (analysis)
• Sneezing
• Structure-Activity Relationship
• Terfenadine (analogs & derivatives, chemistry, pharmacology)
• Therapeutic Irrigation
• Tryptases