Postherpetic neuralgia is neuropathic pain that persists long after the rash and lesions of acute herpes zoster are healed. This patient's history of recent acute herpes zoster infection, in addition to his description of persistent pain and allodynia, leads the NP to conclude that the patient is experiencing postherpetic neuralgia.
Postherpetic neuralgia affects approximately 10% of patients who have had acute herpes zoster infection and is considered one of the most difficult pain syndromes to treat. As many as one half of all patients with postherpetic neuralgia either fail to respond to approved medications or are unable to tolerate the side effects of the medications. Pain that lasts longer than 180 days after the appearance of the acute herpes zoster rash is well established and unlikely to resolve with time and treatment.
The reason that some patients with acute herpes zoster develop postherpetic neuralgia is unknown. The herpes zoster vaccine has reduced by 50% the likelihood of acute herpes zoster infection in immunocompetent individuals older than 60 years, but one half of those who were vaccinated still developed postherpetic neuralgia. Aggressive treatment of an acute outbreak of herpes zoster with nerve blocks and anticonvulsants has been proposed as a method to prevent progression to postherpetic neuralgia, although there is no consensus on this practice.
The sharp, shooting pain of postherpetic neuralgia occurs along the same dermatomes that were affected by the acute herpes zoster infection. In up to 50% of patients, pain is felt across the thoracic dermatomes. Other locations include cranial, cervical, lumbar, and sacral dermatomes. Reports of sensory abnormalities and allodynia are common. Like other chronic pain syndromes, postherpetic neuralgia can impair the individual's functioning and quality of life.
Medscape Nurses © 2012
Cite this: Chris Pasero. The Burning, Searing Pain of Postherpetic Neuralgia - Medscape - Dec 19, 2012.