More young children are getting sick from inadvertently eating marijuana, according to a study published Tuesday in the journal Pediatrics.

According to the study, calls to poison control centers about children under the age of 5 consuming THC-containing edibles increased from 207 in 2017 to 3,054 in 2021, an increase of 1,375%. THC, or tetrahydrocannabinol, is the psychoactive ingredient in marijuana.

Almost all of the children, around 97%, found the groceries at home.

The findings were based on more than 7,000 pediatric cases reported to the National Poisoning Data Systema database that tracks poisoning reports.

The combination of more states legalizing recreational marijuana and the coronavirus pandemic, which meant more kids staying home, likely fueled the rise, said study co-author Dr. Antonia Nemanich, an assistant professor of emergency medicine. and toxicology at Rush University Medical Center in Chicago.

Edibles are often packaged to look like candy or cookies, and children, unaware of the risk they pose, can sometimes eat several at one sitting, Nemanich said.

«They don’t know what it is,» he said, «and they don’t know when to stop.»

Slightly more than half of the reports concerned 2- and 3-year-olds, followed by 4-year-olds (18%), 1-year-olds (15%), and 5-year-olds (13%). study found. Babies accounted for 1.9% of calls.

Eating too much can cause serious health problems in young children, including confusion, hallucinations, a fast heart rate and vomiting, experts said. In severe cases, children may experience trouble breathing or even coma. The severity generally depends on the size and age of the children and the amount of cannabis they have consumed.

“It can be really concerning for the doctors who are treating them,” Nemanich said.

Nearly a quarter of the children were admitted to the hospital, 8.1% of whom needed intensive care, the study found. No deaths were reported.

Dr. Sam Wang, an emergency physician and pediatrician at Children’s Hospital Colorado, said the study reflects what he is seeing at his hospital.

Wang said most of the cases at the Colorado hospital have been «fairly mild,» with children often experiencing drowsiness or loss of balance, though he has seen, on rare occasions, children need ventilators to help them breathe or children who had fallen into a coma. Wang was not involved in the study.

Similar observations have been observed in Philadelphia.

«I think the pattern we’re seeing is well represented in this study,» said Dr. Kevin Osterhoudt, medical director of the poison control center at Children’s Hospital of Philadelphia. «ER physicians across the country have recognized what they believe to be a sharp increase in both young children and adolescents showing to emergency departments for THC poisoning.”

Some manufacturers have begun increasing the THC dose in their edibles, said Osterhoudt, who was not involved in the research. That could lead to an even bigger increase in the number of children getting sick.

A typical edible might contain around 100 milligrams, he said, but even adults often start with a tenth of that. In some states, especially those where recreational marijuana is not legal and unregulated, products can contain up to 500mg of THC, she added.

Wang called for regulation of how marijuana manufacturers can advertise their products, including regulations to ensure that advertising does not attract children.

Parents can protect their children by keeping groceries out of sight, either behind closed doors or high up on shelves, Nemanich said.

«There’s no reason people can’t enjoy these products,» he said. «We just want the kids to be safe.»

Osterhoudt went a step further: «The safest thing for a parent of young children would be not to bring THC edibles into their homes.»

Follow NBC HEALTH on Twitter & Facebook.