As states move from approving medical marijuana laws to allowing recreational use, it doesn’t mean that cannabis should be treated with any less care.

With greater access and availability of marijuana come more unintentional ingestions by children, according to a study published in the journal JAMA Pediatrics.

Medical researchers in Colorado examined children and unintentional exposures to marijuana by comparing data from the last five years as a medical-only state with one year of data after full recreational legalization.

child marijuana exposure

The researchers’ intention was to see the difference in exposure rates following the state’s move to legalize marijuana for recreational use. To date, 23 states have passed medical marijuana laws.

Four states and Washington, D.C., allow marijuana for recreational use.

The researchers used data from Children’s Hospital Colorado in Aurora and from a regional poison center in Colorado from 2009 to 2015.

During that period, 244 children under the age of 10 were admitted with marijuana exposure as the sole need of care.

Two years prior to legalization, marijuana-related visits to the children’s hospital were 1.2 per 100,000 people.

Two years after, that rate rose to 2.3 per 100,000. Poison centers increased from nine pediatric visits in 2009 to 47 in 2015.

Read more: If marijuana is medicine, why can’t we buy it in pharmacies »

Young children most often victims

Marijuana exposure is still low compared to other poisoning methods, such as household cleaning products and alcohol.

However, the incidents do follow a similar pattern.

Most sources of marijuana exposure in Colorado were from parents, and involved edible products not kept in childproof containers.

In addition, researchers said the children generally weren’t well supervised at the time of exposure.

Overall, the median hospital stay for those children was 11 hours, with symptoms of drowsiness, dizziness, agitation, vomiting, and respiratory problems. In a few cases, there were seizures.

“As more states pass laws legalizing recreational marijuana, legislators and healthcare professionals will need to consider strategies to decrease its effect on the pediatrics population,” the authors conclude.

Colorado and Washington were the first states to institute safety measures, including child-resistant packaging, warning labels, dose limitations, and public health campaigns.

Dr. Jordan Tishler of Inhale MD, and a medical marijuana doctor in Massachusetts, says he believes the reporting of numbers is likely compromised, so he’s assuming they don’t reflect reality.

“Only 52 percent of reported cases were linked to edibles. What were the other 48 percent? Two-year-olds lighting up the dab rig? I suspect not,” he told Healthline.

“Overall, between the low incidence, low length of stay, and no long-term negative outcomes, this appears to be not a major public health hazard,” Tishler said. “Additional common sense approaches to preventing such events would be reasonable, but major legislative or regulatory changes seem like an overreaction to the data.”

Read more: Should a worker be fired for using medical marijuana at home? »

Colorado’s legalization landscape

Colorado had two marked surges in marijuana use.

The first was in 2009 when federal authorities announced they wouldn’t be targeting individuals who possess or use marijuana in accordance with their state laws.

This resulted in 60,000 medical marijuana cards being issued in 2009, three times that of all the cards issued in the previous eight years.

The second surge of marijuana users was in 2014 when Colorado became the first state to legalize recreational use.

Some of the same researchers examined trends of pediatric exposures to marijuana while Colorado was still a medical-only marijuana state. The review, published in JAMA Pediatrics in 2013, examined exposures for children under the age of 12.

From January 2005 through September 2009, none of the 790 suspected unintentional ingestions of any substance involved marijuana. From then until the end of 2011, 14 of the 588 ingestions — or 2.4 percent — were from marijuana, according to the study.

The median age for children who accidentally ingested marijuana, in both studies, was between 2 and 3 years old.

Read more: Using medical marijuana doesn’t increase risk of drug abuse »

Important considerations

Parental responsibility plays a large role in preventing marijuana exposure in young children, Tishler said.

He gave the following advice for parents who have marijuana in their homes:

Don’t buy edible products that appeal to kids (e.g. gummy bears)

Don’t eat those products in front of kids.

Use multiple layers of protection: tamperproof containers, out of sight, inside your childproof medicine cabinet.

Assume that kids can open anything, if given enough time.

Watch your children like a hawk.