Prophylaxis and treatment of acute and chronic postherpetic neuralgia

Herpes zoster (HZ) is a disease caused by varicella zoster virus (VZV), where the initial contact leads to varicella. The low immunity of the patient might reactivate the virus and provoke symptoms of HZ, which is characterized by vesicles and blisters localized unilaterally and accompanied by pain. The greatest diagnostic problems occur in Zoster sine herpete and painless HZ. A significant complication of acute HZ infection is chronic postherpetic neuralgia (PHN), which manifests as dull and burning pain persisting for more than 3 months after the beginning of the rash. Senility, female gender, presence of prodromal pain, more severe skin lesions, dysaesthesia, and more intense acute PHN predispose to chronic PHN. Early diagnosis and treatment of HZ infection with antiviral medications prevent PHN. Use of local anesthetics is a very good choice in acute PHN treatment. Tricyclic antidepressants (amitriptyline, nortriptyline) are conventional drugs which alleviate subacute PHN. Immunomodulatory drugs such as gabapentin help prevent or reduce the severity of PHN. The other therapeutic options are RFA (radiofrequency ablation), TENS (transcutaneous electrical nerve stimulation), physical methods such as magnetotherapy and laser therapy. The attenuated vaccine, used in patients over 60 years old, is expected to prevent the occurrence of PHN.