“The itch sensation is a perception”, Dr. Zhou-Feng Chen
The most exciting research regarding itching comes from professor Dr. Zhou-Feng Chen, and his colleagues at the Washington University School of Medicine Pain Center. He is Director, Center for the Study of Itch. To quote from his biography : “Ongoing research program is centered on signalling and synaptic mechanisms of itch transmission from skin to the brain and crosstalk between itch and pain”. While it appears that the team has focussed primarily on mice, the avenue is hopeful for those of us with chronic pain and itching. His work is groundbreaking. It would seem that not only is pain in the brain but so it is with itching.
I have now written 123 blogs on this site about almost every topic I can think regarding fibromyalgia. What has surprised me is the popularity of the 2009 one on itching! Every day the itching site is replete with many searches and comments on that blog. The agony that many suffer from chronic itching has continued to surprise me beyond anything I have read or researched about fibromyalgia. In fact, a person I met recently who has lectured frequently about fibromyalgia had not even mentioned itching on her immense list of symptoms. So, the question on my mind these days is : what can be done to educate the readers about chronic itching, apparently the most aggravating of all challenges of fibromyalgia? What can be said about that which is often called ‘phantom itching’? How can I possibly present information regarding a condition I know so little about? Bear with me folks, I am embarking on a journey attempting to break down the scientific jargon into a more comprehensive language after I have struggled through it myself. The stories and challenges of those of you suffering from chronic itch are heart breaking. I hope I can do you justice.
The itch sensation is caused by a subset of what is known as C-fibers classified as pain-fibers (nociceptors).There is an overlap between itch and pain neurons, therefore because we with fibromyalgia have pain the same neurological systems are activated. The itch neurons are in the peripheral nervous system (PNS) just outside the central nervous system (CNS). In other words, neuropath pain that we experience often causes neuropathic itch. It is the least understood among the somatic senses. While neuropathic pain is more frequent on the face, head and neck, the many comments I have had from readers of this site have complained about the lower extremities and the uppers as well. This syndrome is called “polyneuropathies”. This itching is usually worse in heat and subsides somewhat in cold, and yet rapid changes in temperature can also affect itching (pruritus).Treatment for this itching is not easy as those with fibromyalgia pain taking opioid pain relievers will find the itching becomes worse. Furthermore, neuropathic pain does not respond well to antihistamines. Although I have itching on occasion I believe that because I am taking Gabapentin I seem to have less than my readers. There is some research to suggest that this medication is effective for some and I believe it is for me. Nonetheless, changes in seasons is a difficult time for most of us.
What’s in a name? These are the terms for this chronic itch: “neuropathic itch” (NI) , “pruritus”, “distressing sensory symptoms”, “self- injurious scratching” and even “phantom itching” are terms that are often used inter-changeably. I prefer NI for fibromyalgia itch as it is a disorder of the nervous system, which I have repeatedly written about on this site. Anti-histamines and anti-inflammatories are generally not useful. Once more I urge the readers to practice a daily relaxation strategy, exercise in moderation, undertake a hobby that is new to you, creative and repetitive and most importantly work towards decreasing the stimuli to the nervous system. All of this after being carefully checked out to determine that it is indeed a neuropathic itch due to fibromyalgia.
I also urge you to continue to check out the work of Dr. Chen as it is with he and the rest of his team that we can keep abreast of the newest research about a subject that has been sorely neglected in the past. Also read the old blog I wrote many years ago on the topic as the comments from the hundreds of readers are invaluable.