The effects of prophylactic ondansetron on fentanyl-induced pruritus: a meta-analysis

Objective: The aim of this meta-analysis is to evaluate the effect of ondansetron in the prevention of pruritus after use of intrathecal fentanyl. Methods: The main outcomes were the relative risks (RR) and the 95% confidence intervals (CI) regarding the incidence of pruritus and other side effects. Results: Ten trials totaling 1,084 patients were analyzed. Subgroups results suggested that there was a significant reduction in the incidence of fentanil-induced pruritus compared with control the [RR=0.72, 95% CI (0.56, 0.93)], while there no reduction was detected in the incidence of fentanil-morphine-induced pruritus [RR=1.05, 95% CI (0.94, 1.16)] or ondansetron 8 mg reduced fentanyl-induced pruritus [RR=0.63, 95% CI (0.53, 0.74)]. Conclusions: Prophylactic ondansetron 8 mg may be an effective strategy for preventing fentanyl-induced pruritus, however it may be ineffective in reducing the incidence of fentanyl-morphine-induced pruritus.