Postherpetic neuralgia (PHN) is a complication of shingles, which is caused by the chickenpox (herpes zoster) virus. The condition affects nerve fibers and skin, causing a burning pain that lasts long after the rash and blisters of shingles disappear. There is no known cure for postherpetic neuralgia, but the pain management experts at Novus Spine & Pain in Lakeland, Florida can help you manage the pain.
What Is Postherpetic Neuralgia (PHN)?
Postherpetic neuralgia is a condition of recurring or persistent pain in an area of the body that has undergone an outbreak shingles (the herpes zoster virus).
When the shingles virus damages nerve cells of an infected area, it often causes a painful skin rash that appears as a patch or line of painful blisters on the skin in the shape of a band. The band of blisters follows the distribution of the nerve where the virus was present before it spread to the skin.
Postherpetic neuralgia is a painful condition that often begins after shingles lesions (blisters) begin to crust over and heal, but it may occur when lesions are not produced by the virus.
What Causes Postherpetic Neuralgia?
Postherpetic neuralgia begins when the virus that causes chickenpox affects an individual. After having chickenpox, the virus remains in the body forever. The virus can reactivate, usually decades later, and produce shingles lesions. The reactivation of the virus is thought to be due to stress on the body from either another infection or if the patient’s immune system is compromised (for example, when undergoing treatment for leukemia) that allows the virus to escape the nerve cells.
The nerve fibers damaged from the chickenpox virus are unable to transmit normal sensation messages from the skin to the brain. Instead, the sensation messages become confused and exaggerated, causing chronic, often excruciating, pain that can last months — or even years. However, postherpetic neuralgia does not occur in everyone who suffers from shingles.
What are the Symptoms of Postherpetic Neuralgia?
The signs and symptoms of postherpetic neuralgia are generally limited to the area of your skin where the shingles outbreak first occurred. The most common areas are in a band around the trunk of the body, usually on one side. It may also occur on the face.
The pain associated with postherpetic neuralgia is varied. It can range from discomfort to very severe. The pain is often described as burning, stabbing, or gnawing.
Patients with the condition often can’t bear the slightest touch, even clothing on the affected skin can be painful. In some cases, the sensation may be in the form of either hypersensitivity or decreased sensation. It is rare, but patients may also experience muscle weakness, tremors, or paralysis if the nerves involved also control muscle movement.
How is Postherpetic Neuralgia Diagnosed?
The diagnoses of the majority of patients with postherpetic neuralgia is during a follow-up of a recent shingles infection. During an examination of your skin, the doctor may touch it in places to determine the borders of the affected area.
In most cases, no special tests are necessary.
How is Postherpetic Neuralgia Treated?
Treatment for postherpetic neuralgia depends on the type and characteristics of pain experienced by the patient. Generally, there is not a single treatment of postherpetic neuralgia that relieves pain in all people. In many cases, it takes a combination of treatments to reduce the pain, and ensure patient comfort.
Possible pain management options include:
- Analgesics. Locally applied, a mix of aspirin with an appropriate solvent can help reduce pain.
- Lidocaine skin patches. A small, bandage-like patch containing the topical, pain-relieving medication lidocaine. Apply the patches, available by prescription, directly to the sensitive skin for temporary relief.
- Capsaicin skin patch. The application of a high concentration of an extract of chili peppers (capsaicin) available only in a doctor’s office. Trained personnel apply the patch after using a numbing medication on the affected area. The process takes at least two hours, but a single application is effective in decreasing pain for some patients for up to three months.
- Anticonvulsants. Certain anti-seizure medications can lessen the pain. These medications stabilize abnormal nervous system activity caused by injured nerves.
- Antidepressants. Certain antidepressants affect key brain chemicals that play a role in both depression and how your body interprets pain. Doctors will prescribe antidepressants for postherpetic neuralgia in smaller doses than for depression alone.
- Opioid painkillers. Certain prescription-strength medications can help relieve pain, but must be closely managed by a doctor. Opioids can cause nausea and drowsiness as well as become addictive.
- Steroid injections. A steroid injection into the spine (intrathecal) is helpful in some cases.
Non-drug treatments for postherpetic neuralgia include:
- Acupuncture. The Chinese art of pricking the skin or tissues with very fine needles.
- Moxibustion. A form of heat therapy in which dry plant materials called “moxa” are burned on or very near the surface of the skin. The intention is to warm and invigorate the flow of Qi in the body and dispel certain pathogenic influences.
- Relaxation techniques. These can include breathing exercises, visualization, and distraction.
- Heat/Cold Therapy. Depending on the patient, hot or cold packs may help reduce pain.
- Transcutaneous Electrical Nerve Stimulation. The stimulation of peripheral nerve endings by the delivery of electrical energy through the surface of the skin.
- Spinal cord stimulator. The electrical stimulation of the posterior spinal cord to block nerve impulses.
In some cases, pain treatment for postherpetic neuralgia brings complete relief. However, most sufferers still experience some pain, while some may not obtain any relief. Although some people must live with postherpetic neuralgia the rest of their lives, the condition often disappears on its own within five years.
What are the Risk Factors for Developing Postherpetic Neuralgia?
If you’ve had shingles, you are at a greater risk of developing postherpetic neuralgia, if:
- Age. You’re older than 50.
- Severity. You had a severe rash and severe pain with shingles.
- Other Illness. You have a chronic disease, such as diabetes.
Is it Possible to Prevent Postherpetic Neuralgia?
Zostavax, the herpes zoster vaccine (shingles vaccine), has been shown to significantly 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.
People age 50 to 59 may want to talk to their doctor about the shingles vaccine, if they are having ongoing pain or skin issues or have a weakened immune system. The vaccination is not a guarantee that shingles will not occur; however, those who get the vaccine usually experience a shorter period of pain.
What Are the Risk Factors for Postherpetic Neuralgia?
Age is a high-risk factor for postherpetic neuralgia. The older a person is when shingles develops, the more likely it is that the individual will develop postherpetic neuralgia. People over 60 years of age have about a 60% chance, while people 70 or older have about a 75% chance, of developing postherpetic neuralgia after getting shingles.
People with a family history of close relatives who developed postherpetic neuralgia are at a higher risk of developing this painful condition.
Novus Spine & Pain Center
Novus Spine & Pain Center is in Lakeland, Florida, and specializes in treating postherpetic neuralgia. By using a comprehensive approach and cutting edge therapies, we work together with patients to restore function and regain an active lifestyle, while minimizing the need for opiates.
Postherpetic Neuralgia Resources
Postherpetic Neuralgia Research (Mayo Clinic)
How to Treat Nerve Pain After Shingles (WebMD.com)
Postherpetic Neuralgia (PHN) (MedicineNet.com)
Postherpetic Neuralgia (Wikipedia)
Postherpetic Neuralgia (eMedicine.com)
Post-Herpetic Neuralgia (HealingChronicPain.org)