Characterizing the Toxicity and Dose-Effect Profile of Tramadol Ingestions in Children

Tramadol can cause life-threatening toxicity in overdose; however, data on its toxicity in children are lacking. This study investigates toxicity associated with tramadol ingestions in children. The hypothesis is that children will experience dose-related central nervous system and respiratory depression and seizures.

A retrospective evaluation of cases from the National Poison Center Data System between January 1, 2000, and December 31, 2013, was performed. Inclusion criteria were age below 6 years and single-substance acute tramadol ingestion. For dose-effect analysis, cases with sufficient dose quantity information were included.

There were 7334 cases that met inclusion criteria. Outcomes were 84.8% no effect, 12.6% minor, 2.2% moderate, and 0.4% major effect. There was 1 fatality. Most of the children (36.4%) were treated/released from the emergency department; other management sites were home (36.4%), admission (5.9%), and others (3.2%). In the 1115 children with symptoms, drowsiness (N = 611) and vomiting (N = 178) occurred most frequently. More serious clinical effects included respiratory depression in 36 and seizures in 24 children. Of 2772 children with milligram dose recorded, there were 10 cases of respiratory depression and 6 of seizure. Median doses for respiratory depression and seizure were 225 (range, 50-600 mg) and 525 mg (range, 50-1050 mg), respectively. The minimum weight-based dose for respiratory depression/arrest was 7.9 mg/kg and for seizures, 4.8 mg/kg.

Seizure and respiratory depression are uncommon in pediatric tramadol ingestions. Given the small number of patients with dose data and lack of laboratory confirmation of dose, more studies are needed to determine the minimum dose at which medical management is recommended.