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. 
Patient-preferred* Sarna Sensitive lotion provides the maximum amount of anti-itch medication you can find without a prescription. Itch relief just as effective as 1% topical hydrocortisone (steroidal) creams*, its non-irritating pramoxine hydrochloride (1%) formula moisturizes the skin while soothing the itch. It is ideal for relieving itch associated with eczema and sensitive dry skin. And because it is fragrance- and steroid-free, it is safe for daily use.
*Fleischer A, Johnson K. Comparative efficacy and patient preference of 1% pramoxine lotion and 1% hydrocortisone cream in reducing pruritus in mild atopic dermatitis. Poster presented at: the American Academy of Dermatology 2006 Annual Meeting; March 3-7, 2006; San Francisco, CA.