Comparison of mirtazapine, gabapentin and ondansetron to prevent intrathecal morphine-induced pruritus.

Objective: Antagonism of the central nervous system inhibitor neurotransmitter gamma-Aminobutyric acid (GABA) or serotonergic system activation is an important factor in the pathogenesis of intrathecal morphine-induced pruritus. This study tested the hypothesis that preoperative use of ondansetron, gabapentin or mirtazapine can prevent morphine-induced pruritus.

Methods: We randomly allocated 80 patients of American Society of Anesthesiology (ASA) classification I and II physical status who were to undergo unilateral inguinal hernia or pilonidal sinus operations under spinal anesthesia into 4 equal groups.