J Korean Pain Soc.
2003 Jun;16(1):97-100.
A Case of Mixed Intravenous Infusion of Ketamine and Lidocaine in the Treatment of Post-herpetic Neuralgia
- Affiliations
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- 1Department of Anesthesiology, Inje University College of Medicine, Busan, Korea. jspark@ilsanpaik.ac.kr
Abstract
- Post-herpetic neuralgia is a chronic pain syndrome that develops after an acute herpes zoster infection. The zoster-varicella virus causes damage to all parts of the primary sensory neurons, including the dorsal root ganglion and dorsal horn cell. Peripheral sensitization, and spontaneous ectopic beat discharge, in the C-fiber afferents are necessary to induce central sensitization. After central sensitization, the characteristic symptoms of post-herpetic neuralgia are allodynia, hyperalgesia, and paroxysmal lancinating pain at the involved sites. NMDA receptors play a significant role in the wind-up phenomenon and central sensitization. Blocking of the NMDA receptors abolishes the hypersensitivity in patients with neuropathic pain. Systemic ketamine reduces allodynia and hyperalgesia. Lidocaine blocks the sodium channels and reduces the neuronal excitability in the sensitized C-nociceptors. We present a case of a 72-year-old woman patient suffering from post-herpetic neuralgia who did not respond to conventional treatment, and in whom the administration of a mixed intravenous infusion of lidocaine and ketamine induced adequate pain relief.