5% lidocaine medicated plasters vs. sympathetic nerve blocks as a part of multimodal treatment strategy for the management of postherpetic neuralgia: A retrospective, consecutive, case-series study

Abstract

Introduction

5% lidocaine medicated plasters (5% LMP) have been appointed as a first-line treatment for post-herpetic neuralgia (PHN), while formerly used sympathetic nerve blocks (SNBs) were recently denied their clinical efficacy. The aim of this study was to compare the results of PHN management with the use of SNBs and 5% LMP as a first-line treatment.

Material and methods

This study was designed as a retrospective, consecutive, case-series study. Data of 60 consecutive PHN patients with allodynia treated with the use of SNBs and 60 subsequent patients managed with 5% LMP were analyzed. Pain severity after 8 weeks was assessed to recognize the results of the implemented therapy, with numeric rating scale (NRS) score <3 or =3 considered a success. Additionally, the number of pain-free patients (NRS=0) after 8 weeks were identified in both groups and compared.

Results

The rate of failures in SNBs and 5% LMP group was similar (18.9% vs. 27.1% of poor treatment results, respectively), with the average change in NRS of 5.88±2.41 in nerve blocks and 5.01±1.67 in lidocaine group (p=0.02). Significant difference was also noted in the rates of pain-free patients: 20 patients (34.4%) treated with SNBs and 8 (13.5%) using 5% LMP were pain-free after 8 weeks of treatment.

Conclusion

It may be concluded that SNBs may still be considered useful in PHN management, as it appears that in some cases this mode of treatment may offer some advantages over 5% LMP.