A study of the effectiveness of naltrexone in preventing recurrence of methadone poisoning in opioid-naive children

Background: The prevalence of poisoning from methadone and prescription opioids is increasing in pediatric populations. Naloxone is the main antidote for treatment. Long-acting opioid toxicity may need close observation in the intensive care unit (ICU). In our previous study, naltrexone prevented re-narcotization in methadone-poisoned adults. Here, we aim to share our experience with the use of oral naltrexone for preventing recurrence of toxicity in opioid-naive children. Methods: In a single-center, retrospective case series, children (age <= 12 years) admitted to a poison center in Tehran (Iran) between March 2014-March 2016 were included if they presented with methadone poisoning and received naltrexone treatment in hospital. Naltrexone (1 mg/kg) was administrated orally after initial administration of 0.1 mg/kg naloxone intravenously. Children were monitored for level of consciousness, cyanosis, respiratory rate, VBG results, and O2 saturation for >= 48 h during their hospitalization. Results: Eighty patients with methadone poisoning were enrolled, with median age of three years (range: 0.2-12.0). None involved polysubstance poisoning. Following naltrexone treatment, none experienced recurrent opioid toxicity during hospitalization, and hospital records indicated no readmission within 72-h post-discharge. Conclusion: Oral naltrexone could be a potential substitute for continuous naloxone infusion in methadone poisoned children and reduce the need for ICU care.