Prophylactic Intravenous Ondansetron and Dolasetron in Intrathecal Morphine-Induced Pruritus: A Randomized, Double-Blinded, Placebo-Controlled Study

Abstract

Pruritus is the most common side effect of intrathecal morphine for postoperative pain relief. Activation of central 5-hydroxytryptamine subtype 3 (5-HT3) receptors is one of its possible mechanisms. The role of 5-HT3 antagonists in the prevention of pruritus has not been clearly established. In a prospective, randomized, double-blind, placebo-controlled study, we evaluated the efficacy of prophylactic administration of ondansetron and dolasetron for the prevention of intrathecal morphine-induced pruritus. The patients were randomized into 3 groups to receive either 4 mg ondansetron IV (group O, n = 35), 12.5 mg dolasetron IV (group D, n = 35) or 5 mL placebo (group P, n = 35) 30 min before administration of spinal anesthesia with 10 to 17.5 mg of 0.5% hyperbaric bupivacaine and 0.25 mg of morphine for urologic, orthopedic, or vascular surgery. Patients were evaluated for incidence and severity of pruritus at arrival to the postanesthesia care unit and at 2, 4, 8, and 24 h postoperatively. The incidence and severity of pruritus was significantly less frequent in the ondansetron and dolasetron groups compared with placebo (34%, 20%, and 66% respectively, P < 0.01). Patients who received 5-HT3 antagonist reported significantly less total severity of pruritus compared with placebo during the first 8 h and the severe pruritus was observed only in patients within P group (P group: 4 of 35; 11%, O or D group: 0 of 35; 0%, P < 0.05). We conclude that the prophylactic use of ondansetron and dolasetron helps to reduce the incidence and severity of intrathecal morphine-induced pruritus.

Drug-induced Pruritus: A Review

“…Moreover, nalbuphine was shown to be ineffective in the treatment of postoperative opioid-induced pruritus in paediatric patients (149), The usage of 5-HT3 receptor antagonists (ondansetron, dolasetron) remains controversial. Some authors reported good efficacy (123,141,(150)(151)(152) while others denied it (153)(154)(155). In addition, antihistaminics, droperidol, propofol, alizapride, tenoxicam and diclofenac have been tried with various success (116,124,141,156).…”

Reduction of severity of pruritus after elective caesarean section under spinal anaesthesia with subarachnoid morphine: a randomised comparison of prophylactic granisetron and ondansetron

“…One of the possible mechanisms of pruritus is related to direct stimulation of 5-HT3 receptors by morphine in the dorsal horn of the spinal cord and medulla, therefore 5-HT3 antagonists may be beneficial in its treatment. 10 Previous studies by Yeh et al 4 and Charuluxananan et al 5 demonstrated that prophylactic ondansetron reduced the frequency of pruritus in patients undergoing caesarean section. Conversely, three recent studies 6,7,9 comparing longer acting 5-HT3 antagonists reported the failure of ondansetron, tropisetron and granisetron to prevent pruritus after caesarean section.…”

Manual de práctica clínica basado en la evidencia: Controles posquirúrgicos

“…Los medicamentos específicos son: dolasetrón (reduce el vómito) [23][24][25][26][27] , granisetrón (reduce el vómito) 28-32 y ondansetrón (reduce el vómito y rescates antieméticos) [28][29][30][33][34][35][36][37][38][39][40][41][42][43][44][45] .…”