الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 154 |  |  |
| | | from | 154 | | |
Abstract
The aim of the work is to highlight the best modality, efficacy, possible side effects, and special precautions of ultraviolet phototherapy for pruritus of these diseases. Also, to disclose the main mechanisms involved in the pathogenesis of pruritus in some disorders. Pruritus is “the unpleasant skin sensation that is frequently provokes scratching”. Recent advances in the neurophysiology and molecular basis of itch, has demonstrated that there is a specialized subset of itch-dedicated afferent C neurons. Three scales were developed to assess the severity of pruritus, the 5-D itch scale, the Itch Severity Scale, and the visual analogue scale. Ultraviolet- based therapy has been used to treat various pruritic conditions. Multiple mechanisms hypothesized for the efficacy of phototherapy. In general, it is epidermal keratinocytes and langerhans cells that are affected by UVB, given its limited penetration into the skin. UVA1, in contrast, reaches to the dermis and therefore can affect T lymphocytes, mast cells, and fibroblasts as well as dermal dendritic cells .UVA-induced apoptosis of T cells in the dermis is another mechanism of action of UVA. The method of this work is reviewed essay. Clinical data was collected from reliable medical sources. Main tool used is based on computerized search through medical search web sites. In conclusion after fulfill systemic review, and symptomatic treatment for two weeks, phototherapy might be taken as a second choice in many disorders with chronic pruritus.