Postherpetic neuralgia (post-hur-PET-ik noo-RAL-juh) is a complication of shingles, which is caused by the chickenpox (herpes zoster) virus. Postherpetic neuralgia affects nerve fibers and skin, causing burning pain that lasts long after the rash and blisters of shingles disappear.
The risk of postherpetic neuralgia increases with age, primarily affecting people older than 60. There's no cure, but treatments can ease symptoms. For most people, postherpetic neuralgia improves over time.
The signs and symptoms of postherpetic neuralgia are generally limited to the area of your skin where the shingles outbreak first occurred — most commonly in a band around your trunk, usually on one side of your body. However postherpetic neuralgia is also common in people whose shingles occurred on the face.
Signs and symptoms may include:
- Pain that lasts 3 months or longer after the shingles rash has healed. The associated pain has been described as burning, sharp and jabbing, or deep and aching.
- Sensitivity to light touch. People with the condition often can't bear even the touch of clothing on the affected skin (allodynia).
- Itching and numbness. Less commonly, postherpetic neuralgia can produce an itchy feeling or numbness.
When to see a doctor
See a doctor at the first sign of shingles. Often the pain starts before you notice a rash. Your risk of developing postherpetic neuralgia is lessened if you begin taking antiviral medications within 72 hours of developing the shingles rash.
Once you've had chickenpox, the virus remains in your body for the rest of your life. As you age or if your immune system is suppressed, such as from medications or chemotherapy, the virus can reactivate, causing shingles.
Postherpetic neuralgia occurs if your nerve fibers are damaged during an outbreak of shingles. Damaged fibers can't send messages from your skin to your brain as they normally do. Instead, the messages become confused and exaggerated, causing chronic, often excruciating pain that can last months — or even years.
When you have shingles, you might be at greater risk of developing postherpetic neuralgia as a result of:
- Age. You're older than 50.
- Severity of shingles. You had a severe rash and severe pain.
- Other illness. You have a chronic disease, such as diabetes.
- You had shingles on your face or torso.
Depending on how long postherpetic neuralgia lasts and how painful it is, people with the condition can develop:
- Difficulty sleeping
- Lack of appetite
- Difficulty concentrating
The herpes zoster vaccine (Zostavax) has been shown to greatly decrease the risk of shingles. The vaccine is approved by the Food and Drug Administration for adults age 50 and older and is recommended for all adults 60 and older who aren't allergic to the vaccine and who don't take immune-suppressing medications.