Effects of percutaneous lidocaine administration and xenon-ray irradiation on post-herpetic neuralgia in liver transplant recipients: A report of three cases

(LTRs) with postherpetic neuralgia (PHN). They were referred to our department because of poor pain control. Repeated percutaneous lidocaine (2%, 15 ml) administration to the site of the pain via an iontophoresis system and xenon-ray irradiation were effective for the three patients. Visual analogue scale for pain decreased significantly and requirements of analgesics diminished considerably during the therapy without serious side effects. PHN is relatively common in LTRs, but treatment options are restricted because of immunosuppressive therapy and hepatic and/or renal dysfunction. However noninvasive frequent iontophoretic administration of lidocaine and xenon-ray irradiation produced satisfactory pain relief for PHN in LTRs.