The main purpose of this study is to evaluate the effect of Fumaria Parviflora (FP) on treatment of uremic pruritus of hemodialysis patients. Design: a randomized double- blind placebo-controlled clinical trial. In this study 70 hemodialysis patients (older than 18 years old) with uremic pruritus more than 6 weeks and at least a course of antipruritic therapy without proper response will enroll. After proper informing patients and taking testimonial the patients will be divided in two groups randomly. One group will receive FP (2 capsules three times a day before mealtime for 8 weeks) and one group will receive placebo (2 capsules three times a day before mealtime for 8 weeks). pruritus severity will be assessed by VAS system and DUO questionnaire before and after treatment course and each week during the treatment course. PTH و Hb , BUN , Creatinin, Albumin, ALT, AST, ca, P, PTH, hsCRP, IFN gama , IL4 will be measured before and after treatment course too. Finally two groups will be compared according to changes in their scores of pruritus and the levels of IL4, hsCRP and IFN-gama .