*The following is excerpted from an online article posted on MSN.
A Colorado children's hospital saw four times as many marijuana-intoxicated teenagers land in its ER or urgent care centers following legalization of recreational pot in that state, a new study reports.
The number of teens diagnosed annually with marijuana intoxication or testing positive for pot during a drug screen at Children's Hospital Colorado rose from 146 in 2005 to 639 in 2014.
The findings run counter to national surveys that have shown no increase in teenage pot use in states where recreational marijuana is legal, said lead researcher Dr. George Sam Wang. He's an assistant professor of pediatrics at the University of Colorado Anschutz Medical Campus.
For example, the National Survey on Drug Use and Health found a similar percentage of teenagers reported pot use in 2015 as in the prior decade, researchers said in background notes.
"Our study shows that there have to be other ways we can follow the impact of legalization on the adolescent population," Wang said. "We know that nationwide, marijuana is the most abused drug in the adolescent age group, and there's been a decline in their perception of risk for marijuana use. They think it's not as risky to use it as in years prior."
Eight states and the District of Columbia allow recreational marijuana use. Colorado approved commercialization of medical marijuana in 2010 and legalized recreational marijuana use in 2014.
For the study, Wang and his colleagues reviewed emergency department and urgent care records for 13- to 21-year-olds treated between January 2005 and June 2015. The researchers looked for visits where the patient either had a diagnostic code related to marijuana use or a positive urine screen showing pot in their system.
The rate of emergency department and urgent care visits by stoned teenagers more than doubled -- from 1.7 per 1,000 patients in 2009 to 4 per 1,000 in 2015, said Wang.
Teenagers with symptoms of mental illness accounted for two-thirds of the 3,443 marijuana-related visits detected by the researchers.
Wang agreed that his study does not show that pot caused these kids to need emergency care.
"All it is saying is we are seeing more teenagers coming into the ER or urgent care who are being diagnosed with cannabis abuse or have a urine drug screen positive for marijuana," Wang said.
The study results are scheduled for presentation May 8 at the annual meeting of the Pediatric Academic Societies in San Francisco.