Study Shows That Even a Small Amount of THC Can Have Toxic Effects in Young Children

A new study has revealed the toxic effects of THC, the component in marijuana which triggers a high feeling, in young children.

Since 2017, accidental THC ingestion has skyrocketed in small kids. Scientists set out to deduce which doses require medical intervention, and which cause symptoms for more than six hours. To obtain data, they examined medical records from the Children's Hospital Colorado Network spanning January 2015 to October 2022. 80 accidental ingestion cases in children six and younger were found across four pediatric hospitals and three urgent care facilities.

The results, published Monday in The American Academy of Pediatrics, found that the toxicity threshold is quite low: just under two milligrams of THC per two-point-two pounds of body weight, regardless of age. Since a typical edible contains about 10 milligrams of THC, it would take only two gummies to trigger a toxic reaction in a child weighing 25 pounds.

The average age of patients was just under three years, with nearly 90 percent of cases involving the child discovering the edible at home. A handful of cases, though, resulted from a parent misidentifying the candy as a non-cannabis product. Eight children in the study showed no symptoms. The remainder became symptomatic within one hour, with the most common results being sedation, lethargy, and occasionally vomiting. 34 participants required no medical intervention, but most of them had consumed only about one mg of THC, or less, per pound of body weight.

37 children had at least one toxic reaction after they consumed an average of five-and-one-half mg of THC per single pound of body weight. In these patients, symptoms lasted up to 20.3 hours. Those affected experienced seizures, were hooked up to a ventilator for supplemental oxygen, or given medication to raise their blood pressure. In a few cases, some even lapsed into comas.

"However, these manifestations were rare," the researchers noted. "The dose range to induce these symptoms was two to 69 mg/kg. This wide range suggests other patient characteristics may contribute to the risk of these effects." While the authors don’t elaborate on this, THC is metabolized by the liver and so the wide differential could result from individual liver function.

In order to keep edibles out of the hands of children, experts recommend storing them in a locked, out-of-reach cabinet. They also suggest educating friends and family members on proper edible storage (and consumption) before entering the home.