Legalising marijuana may have unintended consequences. Since medical
marijuana was legalised in Colorado, more than a dozen young children have been
unintentionally poisoned with the drug, researchers report.
About half the cases resulted from kids eating marijuana-laced cookies,
brownies, sodas or candy. In many cases, the marijuana came from their
grandparents' stash, the investigators said.
"We are seeing increases in exposure to marijuana in young paediatric
patients, and they have more severe symptoms than we typically associate with
marijuana," said lead researcher Dr George Sam Wang, a medical toxicology fellow
at the Rocky Mountain Poison and Drug Center in Denver.
But doctors aren't familiar with marijuana poisoning in children, so unless
the parents are forthcoming it can take time and tests to diagnose the problem,
Dangers to children
Symptoms of marijuana poisoning in children include sleepiness and
balance problems while walking.
"We hadn't seen these exposures before the big boom of the medical marijuana
industry," Wang said.
The active chemical in marijuana, tetrahydrocannabinol, is in higher than
normal concentrations in medical marijuana, and often is sold in baked goods,
soft drinks and candies, the researchers said in the study.
"We are seeing more symptoms because some of these products have very high
amounts of marijuana in them," Wang said. "You get such a high dose on such a
small child, the symptoms are more severe."
As with many similar poisonings, treatment is limited to supportive care and
waiting until the marijuana clears the system, he said.
Children recover quickly in most cases, Wang said. "They don't need more than
a day or two of hospitalisation," he said. "There were no deaths or lasting side
This report stems from one Denver hospital, and Wang said he doesn't know how
extensive the problem is elsewhere. Colorado adults are allowed to possess up to
1 ounce of marijuana or six marijuana plants, according to the study. And Denver
issued more than 300 sales tax licenses for marijuana dispensaries in 2010.
Treat it like any other 'drug'
For the study, Wang's team compared the number of children treated in the
emergency room for marijuana poisoning before and after the law was enacted in
In all, almost 1 400 children under 12 were evaluated for accidental
poisonings in this one hospital - 790 before Sept. 30, 2009, and 588 after
After decriminalisation, 14 children - mostly boys and some as young as eight
months - were found to have ingested marijuana. Eight had consumed medical
marijuana, and seven ate marijuana in foods. Two were admitted to the intensive
Before Sept. 30, 2009, none of those possible poisonings was attributed to
marijuana, the researchers found.
There may be more unreported cases, the study authors said. "Because of a
perceived stigma associated with medical marijuana, families may be reluctant to
report its use to health care providers," they wrote in the study.
"Similar to many accidental medicinal paediatric exposures, the source of the
marijuana in most cases was the grandparents, who may not have been available
during data collection," the researchers added.
Eighteen states and Washington, DC, have legalised medical marijuana.
Colorado and Washington also have legalised the recreational use of
In late 2009, the US Justice Department instructed federal prosecutors not to
arrest medical marijuana users and suppliers if they complied with state laws,
the researchers said.
To prevent harm to children, Wang advises treating marijuana like any other
drug and keeping it out of their reach, particularly if it's in a tempting form
like cookies. Some poison-control experts also are pushing for marijuana to come in
tamper-proof packages as a way of keeping children away from it.
The ongoing debate about legalising marijuana should include discussion of
the potential consequences to children, said the researchers and other medical
"There is a lot of information that may not be entirely accurate about how
benign marijuana is," said Dr Sharon Levy, an assistant professor of paediatrics
at Harvard Medical School, who wrote an accompanying journal editorial.
For more information on marijuana, visit the US National
Library of Medicine.