Post-herpetic neuralgia/shingles is pain associated with the reactivation of the varicella zoster virus otherwise known as the chicken pox virus. Anyone who has had the chicken pox has this virus laying dormant in the nerves coming from the spine.
If this virus becomes reactivated, a characteristic shingles rash may emerge, and there may be pain associated with that rash. If the pain persists, even after the rash disappears, one may be diagnosed with post-herpetic neuralgia (PHN).
In the vast majority of patients, there may be slight pain prior to the appearance of the characteristic vesicular rash, although most may not know what to attribute it to. If pain was not experienced prior to the development of the rash, most will feel pain at the immediate onset of the rash or shortly after. In most patients, the pain will go away as the rash heals. In a smaller subset of patients, the pain will persist and will be diagnosed as post-herpetic neuralgia.
The most common area to have a shingles outbreak is along the trunk of the body; however, one could have it on the face, arms or legs. The rash and the pain will coincide with a particular pattern, corresponding to a particular nerve’s distribution of sensation.
Patients may experience a sharp, stabbing pain along the course of the rash during the shingles outbreak, and if the pain continues after the rash has disappeared, some may experience a persistent throbbing pain, intermittent sharp shooting pain, and pain from things that do not normally cause pain (allodynia). An example of allodynia is pain from the wind blowing on the affected area or a bedsheet crossing over the affected area and causing significant pain.
The cause of shingles is well known as the varicella-zoster virus or more commonly known as the chicken pox virus. The likelihood of getting shingles increases as one gets older; however certain populations are also at increased risk such as people with a depressed immune system. This population includes patients with HIV, AIDS, cancer and transplant patients. A particularly stressful time in life could reactivate the virus.
Who goes on to develop post-herpetic neuralgia, or the persistence of the pain, is more unclear. It is thought that increased age and severity of the infection are risk factors for developing PHN.
A shingles vaccine is now available but may not prevent all incidences of the shingles. Once a patient develops the shingles, the main goal is to treat the acute pain and try to prevent PHN. The key is for early administration of antivirals by your primary care doctor. In some patients, a combination of the antivirals and simple pain medication will treat the rash and pain. In other people, it may not, and your primary care provider may refer you to a specialist.
Your doctor at the JLR Center for Pain Medicine will decide on the right care plan for you depending on your symptoms and examination. On initial examination, a thorough history and physical exam will allow us to tailor a plan of care unique to your case.
Early treatment focuses on confirmation of the diagnosis and aggressive treatment to alleviate pain. Your pain management physician will carefully look at the medications that have been prescribed and ensure that you are on the best regimen, which may include a combination of nerve-stabilizing medications, steroids, topical patches and creams, and/or stronger pain medication. Your doctor may also suggest administration of a nerve block or epidural to help alleviate some of the pain. If the pain persists, despite the initial treatment options, your provider may suggest a spinal cord stimulator trial.