This study aimed to explore a dose-response relationship of delta-9-tetrahydrocannabinol (THC) in THC-naïve children after unintentional acute exposure and compare clinical outcomes with non-naïve children.Methods
A retrospective review was performed on children aged 31 days to 20 years who presented to Children's Hospital Colorado for care related to acute THC toxicity. The children were divided into groups based on exposure: group 1 (THC naïve) and group 2 (THC non-naïve).Results
A total of 38 children (age, 3.5  years) met inclusion for group 1 and an equal number of children (age, 15.1 [3.9] years) met the criteria for comparison in group 2. Eight naïve patients had documentation of estimated THC dose ingested (mean [SD], 7.13 [5.8] mg/kg; range, 2.9–19.5 mg/kg). A direct relationship between estimated oral THC dose, level of medical intervention required, and hospital disposition was observed. Lethargy/somnolence was more common in the naïve group (84% vs. 26%, P < 0.0001) whereas problems in cognition, perception, and behavior were more common in the non-naïve group (4% vs 11%, P = 0.01). The duration of clinical effect and length of hospital stay were longer in the naïve group (19.3 vs 5.0 hours, P < 0.0001) and (0.73 vs 0.19 days, P < 0.0001) respectively.Conclusions
There seems to be a direct relationship between the estimated oral THC dose (mg/kg), hospital disposition, and level of medical intervention required. Symptoms and duration of effects after THC exposure varied based on the route of exposure, age of patient, and history of previous THC experience.