Post-Herpetic Neuralgia

What is post-herpetic neuralgia?

Post-herpetic neuralgia is pain that you keep having from shingles long after the shingles rash has healed.

Shingles is an infection of the nerves caused by the varicella-zoster virus, which is the same virus that causes chickenpox. When this virus causes shingles it is called herpes zoster.

Shingles causes pain in the area where you get blisters. For most people the pain fades away in the first month or two after the blisters heal. For some people, the pain stays and can last for months to years. This is post-herpetic neuralgia. The older you are, the more likely you are to have post-herpetic neuralgia. The worse the rash is while you have shingles, the more likely it is that the pain will be severe and long-lasting.

How does it occur?

If you have had chickenpox, you are at risk for later developing shingles. After you recover from chickenpox, the chickenpox virus stays in your body. It becomes inactive (dormant) in a few of the cells of your spinal cord. Later, if your immune system gets weak or very stressed--for example by illness, some medicines, or just normal aging--the virus can become active again. Instead of causing chickenpox again, it causes a painful, blistering rash called shingles. Most people have some pain for a while after the blisters have dried up and gone away. If the pain stays with your for more than 4 months after the blisters heal, you have post-herpetic neuralgia. The pain is due to damage to the nerves.

What are the symptoms?

The pain caused by post-herpetic neuralgia may be stabbing, aching, or burning. It may come and go, or it may be constant. Some people can become overwhelmed and depressed by having to cope with pain every day.

Post-herpetic neuralgia may also result in:

• tiredness
• loss of appetite
• inability to perform your usual daily tasks because of the pain.

How is it diagnosed?

There are no special tests for post-herpetic neuralgia. Your healthcare provider will ask about your pain and if you have ever had chickenpox or shingles.

How is it treated?

A variety of treatments have been tried to ease the pain of post-herpetic neuralgia. What helps one person may not help another. If a treatment does not work, tell your healthcare provider.

Your provider may prescribe:

• an anesthetic cream to put on the painful area (such as EMLA cream or capsaicin cream)
• medicines you take by mouth, such as:
  • acetaminophen
  • narcotic pain relievers
  • antidepressants (especially older tricyclic antidepressants)
  • anticonvulsant medicine, such as divalproex, gabapentin, and pregabalin
• cold packs
• time-release anesthetic patches
• nerve blocks.

When the pain is severe and no combination of medicines works, some studies have shown that injection of steroid and anesthetic medicines into the spinal fluid can give some relief. This is called intrathecal injection. Although this did work well in a couple of studies from Japan, it has not been studied and is not done often in the United States.

How long will the effects last?

Most people have 3 to 6 weeks of pain and then it fades away, but the pain can last for months to years.

How can I take care of myself?

You may find the following helpful:

• Take all medicines as directed by your healthcare provider.
• Let your provider know what in your treatment plan works and what doesn't.
• To keep your immune system strong, eat a healthy diet that is low in saturated fats and includes fruits and vegetables.
• Get enough sleep.
• Get 20 to 30 minutes of aerobic exercise (such as walking or swimming) every day.
• If you are feeling emotionally overwhelmed by the pain, let your provider know. You may want to look for a local chronic pain support group.

How can I help prevent post-herpetic neuralgia?

For prevention of shingles, a vaccine called Zostavax is now available for people 60 years of age and older. This shot helps prevent or lessen the symptoms of shingles. It cannot be used to treat shingles once you have it.

For rapid treatment of shingles, tell your healthcare provider right away if you think you have shingles. If you start taking an antiviral medicine (such as acyclovir) within the first 3 days of the rash, you may be able to avoid some or all of the post-herpetic pain. Some experts believe that antiviral medicines started within 7 days of the rash in people over age 55 may prevent post-herpetic pain.

Some healthcare providers may prescribe corticosteroids such as prednisone to prevent the development of post-herpetic neuralgia as well as to control the pain of shingles. However, researchers who have studied this treatment say that it does not work and probably is not worth the risk of steroid side effects.

One study showed good reduction in the risk of getting long-lasting pain by starting amitriptyline as soon as shingles started. This medicine treats the pain directly, not the virus.

Developed by June Belt-Marchesi, RN, MSN, for RelayHealth.
Published by RelayHealth.
© 2009 RelayHealth and/or its affiliates. All Rights Reserved.