MONDAY, Aug. 28, 2023 (HealthDay News) -- Brightly colored "edibles" can be tempting for young kids and are more widely available now that many U.S. states have legalized cannabis for recreational and medical use.

Unfortunately, it doesn’t take much of an edible to make a small child very sick, new research finds, which may explain an uptick in hospitalizations of kids poisoned by cannabis.

“There are many studies demonstrating a rise in pediatric exposures to cannabis with legalization, and I suspect this trend will continue as legalization spreads,” said study author Dr. Lesley Pepin, an emergency medicine specialist at the Rocky Mountain Poison and Drug Safety in Denver.

A 3-year-old child who weighs around 31 pounds would need to eat just 2.5 milligrams (mg) of the standard 10-mg THC gummies to exceed the toxicity threshold, and a smaller child could become ill after consuming even less, she said. THC is the psychoactive ingredient in marijuana.

Kids can get very sick if they ingest too much THC, she added. Signs of THC poisoning may include seizures, severe altered mental status, unresponsiveness, breathing issues, low blood pressure or fast heart rates.

“Children sick from cannabis require hospital evaluation, medical observation and often need treatments such as supplemental oxygen or IV fluids,” she noted. “The effects can last hours or sometimes beyond a full day.”

Smaller amounts of THC can cause milder symptoms such as sleepiness, nausea or vomiting, difficulty walking and confusion in kids.

For the study, the researchers reviewed hospitalization records for kids under 6 who consumed weed gummies from Jan. 1, 2015, to Oct. 25, 2022. All of the kids were seen at a pediatric hospital network in Colorado, a state with legal recreational and medical marijuana.

During this time, there were 151 cases where kids consumed edible cannabis, and 53% of them met the criteria for “harmful exposure." Kids in the study were about 3 years old, on average, and the typical amount of THC ingested was 2.1 mg.

These children developed symptoms as early as 15 minutes after eating the gummies, with most seeing effects after an hour or two of eating the weed-laced gummy.

“The early signs a parent may notice in a child that ingested a cannabis edible could be symptoms such as sleepiness, nausea or vomiting, difficulty walking, confusion or large pupils,” she said. “It's also possible to see some of the stereotypical signs we associate with marijuana such as red eyes and increased hunger.”

Not all weed gummies are created equally, she said. The amount of THC in a single gummy or edible can vary. A person's age, weight, tolerance of cannabis, medical conditions and other exposures such as alcohol or other drugs also play a role in the potential consequences.

The best way to protect kids is to childproof your weed stash. Edibles should be stored in child-resistant packaging in a locked location out of reach of children, she said. These accidental ingestions often happen outside of the home as well. “Remember to educate family and friends about storing their cannabis products safely as well,” Pepin said.

It’s also important to advocate for improved cannabis product labeling and child-resistant packaging. “Limiting the THC dose sold per package and the attractiveness of these products to children may also help reduce the number of large, accidental overdoses,” she said.

The study was published online Aug. 28 in the journal Pediatrics.

Dr. Tucker Woods is the chair of the emergency department and associate medical director of Lenox Health Greenwich Village in New York City. He has seen his fair share of kids who have gotten into their caregiver's weed gummies. “We are seeing more cases of this, and I expect to see even more now that marijuana is becoming legal in more and more states,” he said.

“These gummies are made for adults who weigh 120 to 160 pounds on average, so for a kid who weighs 28 pounds, one gummy could be enough to cause a coma or seizure,” he said. “The less a child weighs, the greater the risk for ingesting a toxic dose of THC.”

His advice to parents and caregivers is to not have edibles in the house. This isn’t always realistic, so if you do have them, store them safely, he stressed. “Remove the gummies from their packaging, put them in a child-resistant container, label it, and place in a locked cabinet,” he said.

You can also choose edibles with less enticing packaging, he said. “You don’t want it to look like treats, candy or brownies that are naturally appealing to kids, especially those who are too young to read,” he said.

And don't eat them in front of kids, as that will spur their natural curiosity.

Call the poison control hotline if you think your child has ingested edible marijuana. It can be reached at 1-800-222-1222. If your child's symptoms are severe, call 911 or go to the nearest emergency room immediately.

More information

The American Academy of Pediatrics has more on the dangers of edible marijuana for children.

SOURCES: Lesley Pepin, MD, emergency medicine specialist, Rocky Mountain Poison and Drug Safety, Denver; Tucker Woods, DO, chair, emergency department, and associate medical director, Lenox Health Greenwich Village, New York City; Pediatrics, Aug. 28, 2023, online