Department of Pharmacy, The Hospital for Sick Children, Toronto, Canada.
Pediatr Blood Cancer. 2013 Oct;60(10):1667-70. doi: 10.1002/pbc.24615. Epub 2013 Jun 14.
Pediatric oncology patients can experience opioid-induced constipation, which may not respond to laxative treatment. Methylnaltrexone is an opioid receptor antagonist that can reverse opioid-induced constipation without affecting analgesia. Published literature on the use of methylnaltrexone in children is very limited. This retrospective review describes the effectiveness and safety of methylnaltrexone for opioid-induced constipation in pediatric oncology patients.
A retrospective review of health records was conducted for pediatric oncology in-patients who were prescribed methylnaltrexone between May 2008 and September 2012 at The Hospital for Sick Children. Demographic, clinical, efficacy, and safety data were collected, including; opioid, laxative, and methylnatrexone dosing and frequency.
Fifteen patients (median age: 14 years, range: 4-17 years) received methylnaltrexone; 12 received a single dose while three received multiple doses. At the time of methylnaltrexone administration, patients were receiving a median oral morphine dose equivalent of 5.7 mg/kg/day (range: 1.5-29.2 mg/kg/day) and had not had any bowel movements for several days despite treatment with multiple laxatives. Methylnaltrexone was given at a mean dose of 0.15 ± 0.02 mg/kg/dose (range: 3-12 mg/dose) as a subcutaneous injection. After 14 of 19 doses administered, patients had a bowel movement within 4 hours. Three patients had documented mild gastrointestinal upset following methylnaltrexone administration. None reported a reduction of pain control or opioid withdrawal symptoms.
This case series suggests that methylnaltrexone is safe and may be effective when given subcutaneously as a 0.15 mg/kg single dose to pediatric oncology patients with opioid-induced constipation.
儿科肿瘤患者可能会经历阿片类药物引起的便秘，而泻药治疗可能对此没有效果。美沙纳曲酮是一种阿片受体拮抗剂，它可以逆转阿片类药物引起的便秘，而不会影响镇痛效果。目前，关于美沙纳曲酮在儿童中的应用，文献报道非常有限。本回顾性研究描述了美沙纳曲酮治疗儿科肿瘤患者阿片类药物引起的便秘的有效性和安全性。
对 2008 年 5 月至 2012 年 9 月在多伦多 SickKids 医院接受美沙纳曲酮治疗的儿科肿瘤住院患者的健康记录进行了回顾性分析。收集了人口统计学、临床、疗效和安全性数据，包括阿片类药物、泻药和美沙纳曲酮的剂量和使用频率。
15 名患者（中位年龄 14 岁，范围 4-17 岁）接受了美沙纳曲酮治疗；12 名患者接受了单次剂量治疗，3 名患者接受了多次剂量治疗。在给予美沙纳曲酮时，患者的口服吗啡等效剂量中位数为 5.7mg/kg/天（范围 1.5-29.2mg/kg/天），尽管已使用多种泻药治疗，但已连续数天未排便。美沙纳曲酮的平均剂量为 0.15±0.02mg/kg/剂量（范围 3-12mg/剂量），皮下注射。在 19 次给药中的 14 次后，患者在 4 小时内排便。3 名患者在给予美沙纳曲酮后出现轻度胃肠道不适。没有患者报告疼痛控制或阿片类药物戒断症状减轻。
本病例系列研究表明，美沙纳曲酮安全且有效，当用于治疗儿科肿瘤患者阿片类药物引起的便秘时，可给予 0.15mg/kg 的单次皮下剂量。
