The Montreal Children's Hospital is reminding parents to keep their edibles locked up and away from kids following an increase in the number of cannabis intoxication cases.

Between 1990 and 2016, it was relatively rare for doctors at the hospital to treat children under the age of seven who had ingested cannabis — one case, on average, every three years.

But since 2016, when talk of the legalization of marijuana ramped up, nine children under the age of seven have been treated after consuming the drug.

"The average weight of a young kid is about 15 kilos, so an ingestion of a given dose of pot in [someone who weighs] 15 kilos, the effect would be very different than in a patient who weighs 70 kilos," said Dr. Dominic Chalut, pediatric toxicologist at the Children's.

He told CBC Montreal's Daybreak that current theory is that children are more susceptible to cannabis intoxication because they are small and weigh less than adults, but their brains may also be predisposed to be affected by the drug.

The problem, he explained, is that studying the ingestion of cannabis in young kids isn't exactly feasible, so there are questions that still need answering.

Chalut said symptoms to look out for include dizziness, trouble breathing, agitation or lethargy, seizures and nausea, and to seek medical attention immediately if a parent suspects their child has ingested cannabis.

The hospital created an info sheet for parents and guardians with things to remember when it comes to cannabis consumption.

Edibles are expected to be on the legal market by Oct. 17, 2019. He said brownies and gummy bears, especially, can be particularly enticing for children.

"If you're a parent and you know there is pot in your home, keep it safe, probably locked or in a safe environment. You know we don't leave pharmaceuticals on the countertop for kids to have access."