What Is Postherpetic Neuralgia?
Postherpetic neuralgia is a painful condition that affects your nerves and skin. It is a complication of herpes zoster, commonly called shingles.
Shingles is a painful, blistering skin rash caused by a reactivation of a virus called varicella-zoster, which people usually get in childhood or adolescence as chicken pox. The virus can remain dormant in your body’s nerve cells after childhood and can reactivate years later.
When the pain caused by shingles doesn’t go away after the rash and blisters clear up, the condition is called postherpetic neuralgia. Postherpetic neuralgia is the most common complication of shingles, and it occurs when a person’s nerves are damaged during a shingles outbreak. The damaged nerves can’t send messages from the skin to the brain and the messages become confused, resulting in chronic, severe pain that can last for months or years.
According to a study by the American Academy of Family Physicians, about 20 percent of people who get shingles also develop postherpetic neuralgia. Additionally, this condition is more likely to occur in people over the age of 60.
What Are the Symptoms of Postherpetic Neuralgia?
Shingles typically causes a painful, blistering rash. Postherpetic neuralgia is a complication that only occurs in people who already have had shingles. Common signs and symptoms of postherpetic neuralgia include:
- severe pain that continues for more than one to three months in the same place that the shingles occurred, even after the rash goes away
- burning sensation on the skin, even from the slightest pressure
- sensitivity to touch or temperature changes
What Are the Risk Factors for Postherpetic Neuralgia?
Age is a high risk factor for getting both shingles and postherpetic neuralgia. People over 60 have an increased risk, and people over 70 have an even higher risk.
Those who have acute pain and severe rash during shingles are also at a higher risk of developing postherpetic neuralgia.
People with lowered immunity due to disorders like HIV infection and Hodgkin’s lymphoma, a type of cancer, have an increased risk of developing shingles. A study by the American Academy of Family Physicians shows that the incidence of shingles is up to 15 times greater in patients with HIV than in those who don’t have the virus.
How Is Postherpetic Neuralgia Diagnosed and Treated?
Tests are unnecessary. Most of the time, your doctor will diagnose postherpetic neuralgia based on the duration of pain symptoms following shingles.
Treatment for postherpetic neuralgia aims to control and reduce pain until the condition goes away. Pain therapy may include the following treatments.
Painkillers are also known as analgesics. Common analgesics used for postherpetic neuralgia include:
- capsaicin cream: an analgesic extracted from hot chili peppers
- lidocaine patches, a numbing medicine
- over-the-counter medications such as acetaminophen (Tylenol), or ibuprofen (Advil)
- stronger prescription drugs, such as codeine, hydrocodone, or oxycodone
Tricyclic antidepressants are normally prescribed to treat depression, but they are also effective in treating pain caused by postherpetic neuralgia. They often have side effects, like dry mouth and blurred vision. They do not act as quickly as other types of painkillers. Commonly used tricyclic antidepressants to treat postherpetic neuralgia include:
Anticonvulsants are normally used for seizures, however clinical studies have shown that lower doses can be effective in treating pain for postherpetic neuralgia as well. Commonly used anticonvulsants include
How Can Postherpetic Neuralgia Be Prevented?
A herpes zoster vaccine called Zostavax reduces the risk of shingles by 50 percent, and also protects against postherpetic neuralgia. The Centers for Disease Control and Prevention (CDC) recommends that the vaccine be given to all adults over the age of 60, except for people with a weakened immune system. These people may be advised not to receive the vaccine because it contains a live virus.
The herpes zoster vaccine, Zostavax, is different from the chicken pox vaccine, Varivax, that is usually given to children. Zostavax has at least 14 times more live varicella viruses than Varivax. Zostavax can’t be used in children, and Varivax can’t be used to prevent herpes zoster.
Painful, postherpetic neuralgia is treatable and preventable. Most cases disappear in one to two months, and rare cases last longer than a year.
If you’re over the age of 60, it’s wise to get vaccinated against it. If you do develop it, there are many analgesics and even antidepressants you can take to manage the pain. It may just take some time and patience.