What is postherpetic neuralgia?
Postherpetic neuralgia is nerve pain, at the area around where a shingles outbreak occurred, that continues for 3-6 months after the rash from shingles has cleared up.
Postherpetic neuralgia pain may feel burning, stabbing, aching, 'electric', along with itching and extreme skin sensitivity.
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 an infection by the 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 the chances of developing postherpetic neuralgia after shingles. Having multiple risk factors seems to increase the 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 and anxiety.
What are the symptoms of postherpetic neuralgia?
Neuralgia occurs in one part of your body, typically on one side. Postherpetic neuralgia follows the area that was affected by the shingles along the distribution of the specific nerve. The pain may be:
- Sudden, shooting, sharp, burning or stabbing
- Accompanied by a background sensation of burning, itching or aching, or by hypersensitivity to touch
- Continuous or may come and go
- Long lasting - continuing for days, weeks or longer
Seek medical advice about postherpetic neuralgia if:
- You suspect that the pain is caused by a spinal problem, a herniated disc or a pinched nerve.
- You experience pain that is particularly severe or lasts longer than one week. This may develop into postherpetic neuralgia and early treatment may help reduce severity and duration of the pain.
- Facial neuralgia spreads to an eye after a herpes attack; this can lead to blindness if untreated.
- The pain becomes too great to bear.
What are the treatments for postherpetic neuralgia?
There are a number of ways to treat postherpetic neuralgia.
Medications for postherpetic neuralgia
Some of the medications used to treat the symptoms of postherpetic neuralgia are:
- Anticonvulsants. These medications were developed to control seizures but they can also help reduce the pain of postherpetic neuralgia. Gabapentin and pregabalin have been shown to be an effective way to block postherpetic neuralgia.
- Tricyclic antidepressants. This class of antidepressants, such as amitriptyline, has been shown to help ease the pain of postherpetic neuralgia
- Painkillers. Over-the-counter painkillers may be enough for mild cases of postherpetic neuralgia. Many people need more powerful painkillers only available on prescription, such as tramadol.
- Topical treatments. Some people find relief with treatments that are applied directly to the skin
- Capsaicin cream helps with shingles pain and contains the ingredient in cayenne pepper that gives it a kick
- Patches containing the anaesthetic lidocaine can be applied directly to the painful area of skin