The Use of 5% Lidocaine for Prolonged Analgesia in Neuropathic Pain Patients

Park, Sung Wook; Lee, Doo Ik; Kim, Dong Ok; Kim, Keon Sik; Choi, Young Kyu; Kwon, Moo Il; Shin, Kwang Il

Abstract

BACKGROUND
The use of neurolytic agents to control neuropathic pain has been described from the last century. Phenol and ethyl alcohol have been widely used as neurolytic agents, however, their neurolytic effect is variable in efficacy and duration of action, and infrequently accompanied with grave complications. It has been found that 5% lidocaine causes irreversible conduction blockade in animal studies. The goal of this study was to evaluate the neurolytic effect of 5% lidocaine on various neuropathic pain syndromes for prolonged analgesia.
METHODS
Twenty-five patients with a diagnosis of neuropathic pain including trigeminal neuralgia (n = 7), postherpetic neuralgia (n = 10), and postsurgical neuralgia (n = 8) were selected after failure of routine therapeutic regimens. After performing a diagnostic nerve block with 1% lidocaine and 5% lidocaine was injected. The patients were followed for 6 months. Visual analog scale (VAS) scores and side effects were recorded for each patients.
RESULTS
A significant decrease in pain scores after neurolytic blockade with 5% lidocaine was seen in all of three pain groups. All the patients reported immediate and prolonged pain relief lasting from 4 weeks to 6 months. None of patients exhibited any appreciable side effects or complications.
CONCLUSIONS
We suggest that 5% lidocaine may be used safely and effectively for the purpose of prolonged analgesia in selected patients with intractable neuropathic pain syndromes.