Methylnaltrexone proves safety in paediatric oncology patients with constipation

Subcutaneous methylnaltrexone is safe to use in children with cancer who have opioid-induced constipation, suggest the results of a study. In addition, this agent stimulates bowel movements in more than a third of paediatric patients.

Overall, 79 patients received methylnaltrexone in this single-centre study. Of these, seven had data that could not be analysed. Of the 72 patients with available data, 27 (38 percent) were reported as having a bowel movement, and 45 (62 percent) did not have a bowel movement.

Adverse events (AEs) in these patients were minimal. Reported AEs included nausea in three children, flatulence in six, and vomiting in one.

A team of investigators carried out this retrospective study in 79 patients with opioid-induced constipation, who then received methylnaltrexone during their inpatient stay. Data on bowel activity following treatment with methylnaltrexone was acquired using the hospital information system.

The occurrence of a bowel movement within 24 hours after methylnaltrexone administration and the number of bowel movements following treatment served as the primary outcome. Safety in this patient cohort was the secondary outcome.

“Peripherally acting μ-opioid receptor antagonists (PAMORAs) are used in the treatment of opioid-induced constipation without impacting the actions of opioid analgesics,” the investigators said. “Subcutaneous methylnaltrexone was one of the first PAMORAs approved in April 2008 for the treatment of opioid-induced constipation in adult patients.”