[Postherpetic neuralgia].

ABSTRACT

Varicella-zoster virus (VZV) causes two clinically distinct diseases varicella and herpes zoster. Herpes zoster, recurrent infection of VZV occurs when the cell-mediated immunity to VZV declines. Since the cell-medicated immunity to VZV declines with aging, herpes zoster occurs more frequently in the elderly. Most frequent and dreaded complication of herpes zoster is postherpetic neuralgia (PHN). The first line of treatment of PHN is medication with tricyclic antidipressants and anticonvulsants. Double-blind studies showed that effective tricyclic antidepressants for the treatment of PHN are amitriptyline and nortriptyline, and effective anticonvulsants gabapentin and pregabalin. When tricyclic antidepressant and/or anticonvulsant cannot relieve PHN, opioids should be considered in some selected patients. Although neuroablative procedures have been performed for the treatment of PHN, their effectiveness was not confirmed by double-blind studies. They rather aggravate PHN with time. Recent research with a live attenuated varicella vaccine to prevent herpes zoster indicated that the vaccine decreased the occurrence of herpes zoster and postherpetic neuralgia by almost half as compared with placebo. Vaccination of high risk subjects with the varicella vaccine seems to be the most effective measure for the prevention of postherpetic neuralgia.