Q. I suffer from an itchy skin that appears as a wealt my doctor says it is contact dermitis, or is it uticaria I have numerous spots appearing on my neck shoulders elbows and buttocks, they vary from small itchy spots to quite large weals they come and go, I am on antihistamines, but they only give relief occasionally, the weals and terrible itching is worse at night, and I find it difficult to sleep because of the intense itching, my gp says it may be 'contact' dermititis, but I think it may be uticaria, can you help please A. Urticaria (AKA Hives) is the name of this bulging red rush of yours. 'contact' dermatitis is an allergic reaction that can be shown as hives. so it's pretty much the same thing. i suggest try and find out what is the cause of all this- there must be a reason for that allergic reaction. start by when the rash started and what is the material you were exposed to in that area of time.
Noxious input to the spinal cord is known to produce central sensitization, which consists of allodynia , exaggeration of pain, and punctuate hyperalgesia , extreme sensitivity to pain. Two types of mechanical hyperalgesia can occur: 1) touch that is normally painless in the uninjured surroundings of a cut or tear can trigger painful sensations (touch-evoked hyperalgesia), and 2) a slightly painful pin prick stimulation is perceived as more painful around a focused area of inflammation (punctuate hyperalgesia). Touch-evoked hyperalgesia requires continuous firing of primary afferent nociceptors, and punctuate hyperalgesia does not require continuous firing which means it can persist for hours after a trauma and can be stronger than normally experienced. In addition, it was found that patients with neuropathic pain, histamine ionophoresis resulted in a sensation of burning pain rather than itch, which would be induced in normal healthy patients. This shows that there is spinal hypersensitivity to C-fiber input in chronic pain.