Neuropathic pain (NP) is defined by the International Association for the Study of Pain as "pain initiated or caused by a primary lesion or dysfunction in the nervous system." A number of medications (oral or topical) are available for treating NP. Some medications may act by decreasing nerve excitability and conduction in sensory axons. Others may have effects on neural damage-related synaptic changes (particularly for central pain). However,the mechanism of action for various drugs varies substantially and in some cases is not well understood. The purpose of this review is to compare the effectiveness and harms of gabapentin, pregabalin, duloxetine, venlafaxine, and topical lidocaine (patch or gel) for neuropathic pain.

Contents

• Introduction
  • Scope and Key Questions
• Methods
  • Literature Search
  • Study Selection
  • Data Abstraction
  • Validity Assessment
  • Data Synthesis
• Results
  • Overview
  • Results of Search: Systematic Reviews
  • Results of Search: Randomized Trials
  • Key Question 1. What is the comparative effectiveness of pregabalin, gabapentin, SNRIs, and topical lidocaine (patch or gel) to each other for neuropathic pain?
  • Key Question 2. What is the comparative effectiveness of pregabalin, gabapentin, SNRIs, or topical lidocaine (patch or gel) versus other drugs (other antiepileptics, tricyclic antidepressants, selective serotonin reuptake inhibitors [SSRIs], or dextromethorphan) for neuropathic pain?
  • Key Question 3. What are the comparative harms of pregabalin, gabapentin, SNRIs, and topical lidocaine (patch or gel) for neuropathic pain?
  • Key Question 4. What are the comparative harms of pregabalin, gabapentin, SNRIs, or topical lidocaine (patch or gel) versus other drugs (other antiepileptics, tricyclic antidepressants (including tertiary versus secondary amines), SSRIs, or dextromethorphan) for neuropathic pain?
  • Key Question 5. What are the comparative effectiveness and harms of dual therapy with pregabalin, gabapentin, an SNRI, or topical lidocaine (patch or gel) plus a tricyclic antidepressant or another antiepileptic versus monotherapy with a tricyclic antidepressant or another antiepileptic?
  • Key Question 6. Are there differences in effectiveness or harms of drugs used to treat neuropathic pain based on demographics, co-morbidities, or drug-drug interactions?
• Summary
• References
• Appendices
  • Appendix A. Search Strategies for Neuropathic Pain Drugs
  • Appendix B. Quality assessment methods for drug class reviews for the Drug Effectiveness Review Project
  • Appendix C. Criteria for assessing scientific quality of research reviews*
  • Appendix D. Table of Excluded Studies
• Evidence Tables

The funding source, the Center for Evidence-based Policy, is supported by 17 organizations, including 15 state Medicaid programs. These organizations selected the topic and had input into the Key Questions for this review. The content and conclusions of the review are entirely determined by the Evidence-based Practice Center researchers. The authors of this report have no financial interest in any company that makes or distributes the products reviewed in this report.

Suggested citation:

Chou R, Norris S, Carson S, Chan BKS. Drug Class Review on Drugs for Neuropathic Pain. 2007. http://www.ohsu.edu/drugeffectiveness/reports/final.cfm

The Agency for Healthcare Research and Quality has not yet seen or approved this report.

The purpose of this report is to make available information regarding the comparative effectiveness and safety profiles of different drugs within pharmaceutical classes. 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.