Understanding postherpetic neuralgia - the basics

What is postherpetic neuralgia?

Neuralgia is nerve pain that occurs when a nerve is irritated or inflamed. The pain spreads along neural pathways, may be brief or chronic, and can range from mild to outright unbearable.

A relatively common type of neuralgia is postherpetic neuralgia, which strikes after the infection known as shingles (herpes zoster). Typically people with this form of neuralgia experience a continuous burning sensation. Pain may be very severe and long lasting. Any pain that persists for more than a month after resolution of the herpes zoster rash is called postherpetic neuralgia.

What are the causes of postherpetic neuralgia?

The most likely source of any neuralgia is irritation or inflammation of a nerve or pressure on a nerve from bones or connective tissue. In postherpetic neuralgia the nerve inflammation is caused by a infection by varicella-zoster virus, the same virus that causes chickenpox.

Not everyone who has shingles is stricken with the pain afterwards. But as many as 20% to 30% do go on to develop postherpetic neuralgia.

Doctors have identified a number of factors that increase your chances of developing postherpetic neuralgia once you have shingles. Having multiple risk factors seems to increase your chances of getting postherpetic neuralgia. They include:

• Older age
• Being a woman
• Presence of symptoms before the rash appeared such as numbness, tingling, itching,or pain
• Severity of pain during initial stages of the illness
• Severity of rash

Psychological stress may also play a role. One study found that people who developed postherpetic neuralgia were more likely to have had symptoms of personality disorders, anxiety and other bodily symptoms.