Significantly more children in Colorado have been treated for unintentional exposure to marijuana since recreational pot became legal there, according to a new study published Monday. The findings offer a cautionary tale for California, where voters will decide in November whether to legalize recreational use of the drug.
Experts thought there would be "a little bit of an increase," but "I think what caught us by surprise was how many more exposures we saw after the legalization of recreational marijuana," said Dr. Genie Roosevelt, the study's senior author and an associate professor of emergency medicine at the University of Colorado.
The study, published in JAMA Pediatrics, is the first to analyze the impacts of legalized recreational marijuana on pediatric exposure, she said.
The authors analyzed visits to Children's Hospital Colorado in Aurora and calls to the regional poison center that serves the state between Jan. 1, 2009 and Dec. 31, 2015. Both institutions registered jumps in marijuana exposures in 2014 and 2015, after recreational pot became legal in Colorado in Jan. 2014.
According to poison center data, the number of marijuana exposure cases among kids under 10 averaged about 15 a year from 2009-13, and jumped to 40 in 2014 and 47 in 2015, according to the study. The rate of increase in Colorado was significantly higher than in the rest of the country, it found.
There were an annual average of six exposure cases at Children's Hospital Colorado in the five years between 2009 and 2013, the study said. That jumped to 16 in each of the first two years of legal recreational pot, it noted.
About half of the poison center and hospital cases were attributed to edible products.
The study's authors point out that kids are still more likely to accidentally ingest pharmaceuticals or household products, because they're more commonly found in homes. But the researchers say edible marijuana products pose a "unique problem," because "no other drug is infused into a palatable and appetizing form" - such as cookies, brownies and candy.
Roosevelt has advice for California and other states weighing legalizing recreational marijuana: "Really think about the forms and limit the candy options, so it doesn't really look like typical candy, to try to make it less enticing to children," she said.
The authors also conclude that child-resistant packaging has not been as effective as they had hoped it would be in reducing kids' unintended exposure to pot.
"People should think of recreational or medical marijuana products as a medication," Roosevelt said. Child-proof packaging "has to be accompanied by education for the community, so that they really do treat these products as medication," she added.
Of the 62 patients evaluated at Children's Hospital Colorado between Jan. 1, 2009 and Dec. 31, 2015, 13 were admitted to an inpatient unit and nine were admitted to an intensive care unit. Two patients required respiratory support.
The average age of these patients was about 2 1/2, the study said. Parents were the most common source of the marijuana.
The average age of the 163 poison center cases was 2. Most were referred to or treated at a health care facility. The most common symptoms kids experienced were drowsiness and lethargy, according to the researchers. The study did not state whether any of the cases required hospitalization; it did note that 18 children experienced "moderate effects" and four experienced "major effects."
Prop. 64, the November ballot initiative that would legalize recreational pot in California, includes safeguards intended to prevent kids from ingesting marijuana. It says all pot products should be designed so as not to be appealing to children or easily confused with candy or foods that don't contain marijuana.