Evaluation of Antipruritic Effect of Melatonin on Hemodialysis Patients with Uremic Pruritus, A Double-Blind, Randomized, Crossover Trial

Introduction. Uremic pruritus (UP) is one of the major complaints in hemodialysis patients without specific treatment. Considering the antipruritic effect of melatonin in atopic dermatitis (AD) and similarities in mechanism between pruritus in AD and UP, this randomized clinical trial designed to evaluate the antipruritic effect of melatonin on hemodialysis patients with UP. Methods. This multicenter double-blind randomized clinical trial was conducted among the hemodialysis patients with UP. Adult patients were randomly assigned to receive two capsules of melatonin 5 mg / d for a 2 weeks period, undergoing a 1 week washout period, and then two capsules of placebo for another 2 weeks period, or the reverse sequence. Visual Analogue Scale (VAS), % affected Body Surface Area (%BSA) and 12-Pruritus Severity Scale questionnaire (12-PSS) were measured before and after each of the three periods. A crossover analysis of variance adjusted by treatment, period and carryover effect was performed by STATA 14. Results. Thirty-nine patients under hemodialysis (mean age of 55.08 +/- 12.34 years) completed the study. Mean changes in VAS, 12-PSS, and %BSA after the interventions (melatonin vs. placebo, mean +/- SD) were as follows, respectively: -3.21 +/- 3.33 vs. -1.38 +/- 2.23, -4.59 +/- 5.22 vs. -2.08 +/- 4.35, and -19.10 +/- 30.31 vs. 4.64 +/- 29.11 (P < .05). However, the statistical significance of the treatment effect from melatonin was observed, carryover and period effects were not significant (P > .05) for any of the main variables. Conclusion. Based on to the preliminary results of this study, melatonin can be introduced as an effective drug for management of pruritus in uremic patients.