Treatment for allergic rhinitis and chronic idiopathic urticaria: focus on oral antihistamines.
OBJECTIVE
To review the efficacy and safety of first- and newer-generation antihistamines for the management of allergic rhinitis and chronic idiopathic urticaria (CIU), with a focus on management in the pharmacy.


METHODS
A literature review was performed using MEDLINE (1966-October 2005), with no time or language restrictions. Key words or phrases used were histamine, antihistamine(s), first- and second-generation, allergic rhinitis, chronic idiopathic urticaria, quality of life, impairment, sedation, cost-effectiveness, astemizole, cetirizine, desloratadine, diphenhydramine, fexofenadine, loratadine, hydroxyzine, ketotifen, and mizolastine. Additional references were found in the bibliographies of the articles cited.


METHODS
Clinical trials and other experimental studies of the use of antihistamines for the management of allergic rhinitis and CIU were selected. Review papers and guidelines were also included.


RESULTS
First-generation antihistamines are effective at ameliorating the symptoms of allergic rhinitis and CIU; however, they are associated with adverse effects due to a lack of selectivity for the histamine H(1)-receptor and an ability to bind to cerebral H(1)-receptors. Newer-generation agents, in general, possess high H(1)-receptor selectivity and a low tendency to cross the blood-brain barrier, while maintaining efficacy. In general, safety at elevated doses has been demonstrated for the newer antihistamines, although higher rates of sedation and impairment have been reported with increasing doses for some agents.


CONCLUSIONS
Pharmacists can play an important role in the management of allergic rhinitis and CIU by considering the relative advantages of newer-generation agents when reviewing treatment options.
Morgan
Matthew M
MM
Asthma and Immunology of North Texas, McKinnney, USA.
Khan
David A
DA
Nathan
Robert A
RA
D002908:Chronic Disease; D003362:Cost-Benefit Analysis; D006633:Histamine Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D006255:Rhinitis, Allergic, Seasonal / Q000188:drug therapy* / Q000191:economics / Q000503:physiopathology; D014581:Urticaria / Q000188:drug therapy* / Q000191:economics
D006633:Histamine Antagonists