We all know the saying -- once you’ve had the chickenpox, you can never get them again. That’s because most people will develop antibodies to protect them from future outbreaks. What you might not know, is that the virus can remain inactive in our bodies for decades. For 30% of the population, there’s a risk of this virus reactivating; instead of chickenpox, however, the same virus manifests as shingles.
Shingles results in a painful rash which can last between 2-4 weeks. If pain persists once the rash has cleared, postherpetic neuralgia
, or nerve pain, could be the cause. This is likely to happen to 6.5% of individuals with shingles, with the incidence of postherpetic neuralgia increasing with age.
One of the common approaches to pain management for postherpetic neuralgia is lidocaine. Lidocaine skin patches, and other topical agents
, help to numb nerve cells so that chronic nerve pain can’t be felt. But what does the research say about using lidocaine to treat this kind of pain?
What kind of research was done?
In July 2014, a Cochrane Database Systematic Review, looking at topical lidocaine for neuropathic pain in adults, was published by Derry, Wiffen
and Moore. The review assessed whether or not substantial evidence exists to suggest that lidocaine should be prescribed to individuals with postherpetic neuralgia.
Two research reviewers independently assessed studies published up until July 2014. The research reviewed consisted of randomised, double-blind studies, each lasting at least 2 weeks. In total, 12 studies were reviewed, representing a total of 508 participants. Half of the studies looked at individuals with moderate to severe postherpetic neuralgia, while the rest were studies of individuals at various stages of the condition. The different studies looked at a variety of lidocaine products (medicated patch, cream, gel and spray); studies also varied in duration, treatment programs and pain assessment.
What were the results?
Unfortunately, the review found that the studies dealing with this question weren't comparable enough to combine data or pool results. In addition, each of the original study participant groups were too small to draw any conclusions without a risk of bias.
The bottom line
- To date, no high quality evidence has been produced to support the use of lidocaine to treat postherpetic neuralgia.
- Large, ongoing studies of adequate duration are needed before lidocaine takes a leading role in pain management.
- The review also notes that individual studies and clinic experience have pointed towards lidocaine being useful in managing this condition. The side effects associated with lidocaine are also quite minimal, so talk to your doctor about whether or not lidocaine might be right for your pain management plan.
Have you used lidocaine to help manage postherpetic neuralgia? Leave a comment below and let us know how it worked for you.
Derry S, Wiffen PJ, Moore RA, et al. Topical lidocaine for neuropathic pain in adults. Cochrane Database Syst Rev. 2014 Jul 24;7:CD010958. doi: 10.1002/14651858.CD010958.pub2. (Review) PMID: 25058164
Public Health Agency of Canada. Canadian Immunization Guide: Herpes Zoster (Shingles) Vaccine. [Cited 2014 Sept 16]. Available from: http://www.phac-aspc.gc.ca/publicat/cig-gci/p04-herp-zona-eng.php
Opstelten W1, Mauritz JW, de Wit NJ, van Wijck AJ, Stalman WA, van Essen GA. Herpes zoster and postherpetic neuralgia: incidence and risk indicators using a general practice research database. Fam Pract. 2002 Oct;19(5):471-5.