How to prevent postherpetic neuralgia

摘要

Herpes zoster (HZ) is a neuro-cutaneous disease caused by the reactivation of Varicella-zoster virus (VZV) in sensory ganglia. The infection affects millions of older adults annually worldwide. Zoster associated pain (ZAP) presents significant patients' suffering in the acute phase of disease and even more if it continues under the picture of postherpetic neuralgia (PHN). PHN is the most common complication of herpes zoster affecting 8 -12% of subjects with HZ when observed more than 90 days after the onset of rash and rated as 3 or more on a scale from 0 to 10. The point of transition from the acute condition to PHN can be difficult to define making the choice of the appropriate therapy problematic. PHN is defined in few arbitrary manners and range from 1 month to 6 months after the rash. The most common definition is neuralgia of 3 months or more after HZ.The risk factors for acute zoster pain and PHN differ. The risk factors for PHN jet have not been clearly established and so far the prevention of postherpetic neuralgia is still unsatisfactory. Identification of possible medical, biological, and psychosocial factors could improve PHN prevention.