Children who accidentally eat food such as cookies made with marijuana can get sick, according to a new study. Researchers at Colorado Children’s Hospital report they treated 14 children who ingested the drug, half of whom ate marijuana-laced foods.

Symptoms, most of which were mild, included unusual drowsiness and unsteady walking. One 5-year-old boy had trouble breathing. Eight children were hospitalized, and two were treated in the intensive care unit, according to the Associated Press. All of the children recovered within a few days.

“Physicians, especially in states that have decriminalized medical marijuana, need to be cognizant of the potential for marijuana exposures and be familiar with the symptoms of marijuana ingestion. This unintended outcome may suggest a role for public health interventions in this emerging industry, such as child-resistant containers and warning labels for medical marijuana,” the authors write in the journal JAMA Pediatrics.

In an accompanying editorial, William Hurley, MD from the Washington Poison Center, and Suzan Mazor, MD, from Seattle Children’s Hospital, wrote, “The legalization of recreational marijuana, especially the solid and liquid-infused forms permitted in Washington, will provide children greater access to cookies, candies, brownies, and beverages that contain marijuana.” They note ingesting marijuana leads to stimulation with hallucinations and illusions, followed by sedation. They say additional training is needed for emergency medicine, pediatric emergency medicine and primary care pediatric physicians to recognize and manage these toxic reactions.