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Drug Class Review: Newer Antihistamines

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Drug Class Review: Newer Antihistamines Drug Class Review Newer Antihistamines Final Report Update 2 May 2010 The purpose of Drug Effectiveness Review Project reports is to make available information regarding the comparative clinical effectiveness and harms of different drugs. Reports are not usage guidelines, nor should they be read as an endorsement of or recommendation for any particular drug, use, or approach. Oregon Health & Science University does not recommend or endorse any guideline or recommendation developed by users of these reports. Original Report: November 2004 Update 1: April 2006 The literature on this topic is scanned periodically. Update 2 prepared by: Susan Carson, MPH Nancy Lee, PharmD Sujata Thakurta, MPA:HA Drug Effectiveness Review Project Marian McDonagh, PharmD, Principal Investigator Oregon Evidence-based Practice Center Mark Helfand, MD, MPH, Director Oregon Health & Science University Copyright © 2010 by Oregon Health & Science University Portland, Oregon 97239. All rights reserved. Final Report Update 2 Drug Effectiveness Review Project The medical literature relating to this topic is scanned periodically. (See http://www.ohsu.edu/ohsuedu/research/policycenter/DERP/about/methods.cfm for description of scanning process). Prior versions of this report can be accessed at the DERP website. Antihistamines Page 2 of 72 Final Report Update 2 Drug Effectiveness Review Project TABLE OF CONTENTS INTRODUCTION .......................................................................................................................... 6 Purpose and Limitations of Systematic Reviews..................................................................................... 9 Scope and Key Questions..................................................................................................................... 11 METHODS.................................................................................................................................. 12 Study Selection and Inclusion Criteria................................................................................................... 12 Populations ....................................................................................................................................... 12 Interventions...................................................................................................................................... 12 Outcomes.......................................................................................................................................... 12 Study Design..................................................................................................................................... 13 Literature Search................................................................................................................................... 13 Data Abstraction.................................................................................................................................... 13 Study Selection ..................................................................................................................................... 14 Validity Assessment .............................................................................................................................. 14 Data Synthesis ...................................................................................................................................... 15 Public Comment .................................................................................................................................... 15 RESULTS ................................................................................................................................... 15 Overview ............................................................................................................................................... 15 Key Question 1. For outpatients with seasonal or perennial allergic rhinitis or urticaria, do newer antihistamines differ in effectiveness?................................................................................................... 17 Detailed Assessment ........................................................................................................................ 18 Adults ................................................................................................................................................ 18 Seasonal allergic rhinitis ............................................................................................................... 18 Direct evidence......................................................................................................................... 18 Indirect evidence ...................................................................................................................... 20 Perennial allergic rhinitis............................................................................................................... 20 Direct evidence......................................................................................................................... 20 Indirect evidence ...................................................................................................................... 20 Urticaria ........................................................................................................................................ 20 Direct evidence......................................................................................................................... 20 Indirect evidence ...................................................................................................................... 22 Children............................................................................................................................................. 23 Seasonal allergic rhinitis ............................................................................................................... 23 Perennial allergic rhinitis............................................................................................................... 23 Urticaria ........................................................................................................................................ 26 Key Question 2. For outpatients with seasonal or perennial allergic rhinitis or urticaria, do newer antihistamines differ in harms?.............................................................................................................. 26 Summary of findings ......................................................................................................................... 26 Detailed assessment......................................................................................................................... 27 Adults ................................................................................................................................................ 27 Total withdrawals and withdrawals due to adverse events........................................................... 27 Commonly reported adverse events............................................................................................. 27 First-generation antihistamines compared with newer antihistamines ......................................... 27 Cetirizine compared with loratadine ......................................................................................... 27 Levocetirizine compared with desloratadine ............................................................................ 28 Cetirizine compared with fexofenadine .................................................................................... 28 Desloratadine compared with fexofenadine ............................................................................. 28 Astelin nasal spray compared with olopatadine nasal spray.................................................... 28 Azelastine nasal spray compared with cetirizine...................................................................... 29 Electrocardiogram changes .......................................................................................................... 29 Other............................................................................................................................................. 29 Antihistamines Page 3 of 72 Final Report Update 2 Drug Effectiveness Review Project Children............................................................................................................................................. 29 Total withdrawals and withdrawals due to adverse events........................................................... 29 Commonly reported adverse events............................................................................................. 29 Electrocardiogram changes .......................................................................................................... 30 Other............................................................................................................................................. 30 Key Question 3. Are there subgroups of patients based on demographics (age, racial groups, gender), concomitant medications (drug-drug interactions), co-morbidities (drug-disease interactions or pregnancy), for which one newer antihistamine is more effective or associated with fewer harms? .... 31 Summary of findings ......................................................................................................................... 31 Detailed
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