Anesthesiology. 2021 Aug 1;135(2):350-365. doi: 10.1097/ALN.0000000000003844.
Opioids are a mainstay of treatment for pain worldwide. Pruritus, a common side effect of opioids, is a patient dissatisfier that limits their use in many clinical settings. Both parenteral and neuraxial administration of opioids frequently evoke pruritus. The ability of opioids to suppress pain while causing itch continues to perplex clinicians and researchers alike. Several mechanisms have been proposed to explain how opioids can give rise to pruritus, but specific knowledge gaps perpetuate debate. This review summarizes the clinical burden of opioid-induced pruritus and emphasizes recent discoveries of peripheral and central mechanisms for opioid-induced pruritus, particularly with respect to scientific and conceptual advances in spinal cord circuitry and mast cell biology. The mechanisms and effectiveness of existing medications used for clinical management of pruritus will be evaluated, and we will highlight the emerging preclinical utility of selective κ-opioid receptor agonists, such as nalfurafine, for the management of opioid-induced pruritus.
阿片类药物是全球治疗疼痛的主要药物。瘙痒是阿片类药物的常见副作用，是一种令患者不满的药物不良反应，限制了它们在许多临床环境中的使用。阿片类药物的注射和鞘内给药常常会引起瘙痒。阿片类药物既能抑制疼痛，又能引起瘙痒，这一现象一直令临床医生和研究人员感到困惑。已经提出了几种机制来解释阿片类药物如何引起瘙痒，但特定的知识空白仍在继续引发争论。本综述总结了阿片类药物引起的瘙痒的临床负担，并强调了外周和中枢机制的最新发现，特别是在脊髓回路和肥大细胞生物学方面的科学和概念进展。将评估现有用于瘙痒临床管理的药物的作用机制和效果，并将重点介绍选择性 κ-阿片受体激动剂（如纳呋拉啡）在管理阿片类药物引起的瘙痒方面的新兴临床前应用。
