Out-of-state visitors who used marijuana ended in the emergency room at double the rate of Colorado residents, according to researchers at CU's School of Medicine and Northwestern Medicine.
The study took place in the University of Colorado Hospital ER.
Researchers examined emergency rooms visits before and after recreational marijuana was legalized in 2014. Their findings suggest that other states considering legalization "need to implement preemptive public health education efforts," said CU’s Dr. Andrew Monte, the senior author of the study.
According to the report, out-of-state visitors to the ER for marijuana-related symptoms accounted for 78 out of every 10,000 emergency room visits in 2012. That ratio climbed to 163 out of every 10,000 visits in 2014, a for an increase of 109 percent.
The study did not go into detail on whether the ER visits were the result of smoking marijuana, or consuming edibles, according to lead investigator Dr. Howard Kim, a postdoctoral fellow in emergency medicine at Northwestern. But he said the edibles -- in candy, cookies and other products -- have a delayed effect, which could lead to overdosing, Kim said.
“People eating marijuana products often don’t feel any effect immediately, leading them to eat another edible,” Kim said in a statement accompanying the study's release. “Then they’ve ingested multiple products, so when the effect finally kicks in, it is much stronger.”
Colorado launched a nearly $6 million public education campaign last year about responsible marijuana use called “Good to Know.”
The report is published in the New England Journal of Medicine.