Unintentional Marijuana Exposure Presenting as Altered Mental Status in the Pediatric Emergency Department: A Case Series

Unintentional tetrahydrocannabinol (THC) exposure in pediatric patients can present as altered mental status. Altered mental status in a pediatric patient often leads to invasive diagnostic testing. The following cases describe 3 pediatric patients in Washington state who presented to a tertiary care children's hospital emergency department (ED) with altered mental status, later found to have urine toxicology screening positive for inactive THC metabolite (positive THC toxicology screen). Case 1 is a 6-year-old boy who presented with vomiting, lethargy, and hallucinations. Case 2 is a 5-year-old girl who presented with nausea, slurred speech, ataxia, and lethargy in the setting of a minor head injury. Case 3 is a 7-month-old boy who presented with vomiting and lethargy in the setting of a minor fall the day prior to ED evaluation. All children had extensive work-ups before the diagnosis was made; 2 were discharged home and 1 was admitted to the pediatric intensive care unit. As access to marijuana increases with growing legalization, it is important to be familiar with state marijuana legislation, to consider and ask families about access to marijuana products as a potential contributor to altered mental status, and to be aware of potential caretaker reluctance regarding disclosure of marijuana use secondary to perceived stigma. Maintaining awareness of the clinical effects of THC exposure in children may limit invasive testing in a hemodynamically stable child with altered mental status.