[Postherpetic neuralgia]

Postherpetic neuralgia is considered to be a neuropathic pain syndrome. Typically, patients experience pain in the dermatomes of skin lesions persisting for more than 3 months after skin restitution. About 10 % of patients with herpes zoster develop postherpetic neuralgia. Its prevalence increases with age. Common clinical symptoms include continuous burning pain, sharp pain attacks, and allodynia. Additionally, sensory hyperactivation or loss in the affected skin area is present. Pathophysiology includes mechanisms of peripheral and central sensitization, based on damaged nerve fibers as the main mechanisms for pain generation and its maintenance. Clinical studies did show pain relief in postherpetic neuralgia after administration of antidepressants, antiepileptic drugs, opioids, and topical capsaicin and lidocaine. Nevertheless, about one third of patients do not respond to conventional treatment. Given the fact that postherpetic neuralgia is considered to be a chronic pain disease, a multidisciplinary treatment approach is necessary.