|
SELECTED ARTICLES FROM THE RECENT LITERATURE 2006
10/16/06
Efficacy and CNS impairment of newer generation antihistamines
Summary
Background – It is generally recognized that the more recently developed H-1 antihistamines (AH) are usually much less likely to affect cognitive function than older AH such as diphenhydramine (Benadryl) and chlorpheniramine (Chlor-Trimeton). But are these newer AH equally effective? Do they have a similar likelihood of causing adverse cognitive effects?
Findings – This subject was reviewed by Spangler and Brunton of Atlanta, GA. They concluded that newer AH available for use in practice such as fexofenadine (Allegra), cetirizine (Zyrtec) and desloratadine (Clarinex) have approximately similar efficacy in controlling symptoms of seasonal allergic rhinitis in adults and children. However, cetirizine is more likely to cause sedation and other adverse cognitive effects.
Reference
South Med J 2006;99:593-9
Editor's Comments
These comments are in line with that expressed by many experienced clinicians. In blinded studies, sedation has occurred in 10-14% of young, otherwise healthy subjects taking cetirizine in the standard 10 mg/day dose. In contrast, sedation is very unusual (generally less than 2%) during fexofenadine therapy even when twice the usual 180 mg/day dose is taken by adults, not significantly different than seen with placebo therapy. I personally have found fexofenadine to be effective more often than desloratadine in the treatment of allergic rhinitis. However, there is considerable variation from patient to patient in the clinical efficacy of each of these newer AH agents in the treatment of allergic rhinitis.
|