The 5-year-old girl lay limp in her father’s arms, fast asleep, as he rushed her into the doors of the pediatric emergency department.

“We can’t wake her up,” he pleaded, eyes wide and voice rushed with desperation.

“Maddie’s never slept this deeply. It’s strange,” he continued frantically. “She fell asleep in the car on the way home from camping. We yelled, pinched her, splashed cold water on her face. She just stays zonked.”

She looked like Sleeping Beauty; her cheeks were pink and her breathing comfortable, yet her eyes remained closed. I rubbed her breastbone with my knuckle — a trick that usually wakes kids up — and she didn’t flinch or awaken. A thorough physical exam revealed no signs of injury or illness. Her heart rate, blood pressure, and oxygen levels were perfectly typical for her age. She was simply unrousable.

In children, this kind of unresponsiveness most often comes from ingesting something — an accidental overdose of a medication or an illicit drug. Thus, our first treatment was Naloxone, which reverses the effects of opioids. We sprayed a hefty dose up her nose. She remained still. We tried a second dose. No response again.

Still, Maddie’s other blood tests all checked out. Normal levels of glucose and other electrolytes, no damage to the liver or kidneys, no alcohol or elevated levels of common medications like Tylenol or aspirin. Her parents were adamant there was little in their home she could have gotten into: no prescribed medications, no marijuana, no liquor. The only things in their cabinets were some antibiotic ointment and over-the-counter allergy medicine.

“And we haven’t even been home for the last three days,” her mother said, tearfully, “We were camping up in the mountains. We all ate the same food. She never fell or hit her head. We were together the whole time. She seemed fine. She’s always been so healthy.”

A scan of Maddie’s brain was also completely normal, with no signs of bleeding, a broken skull, fluid in the brain, a tumor, or other signs of infection. I carefully put a needle between the bones of her back to get a sample of spinal fluid. She didn’t flinch. All tests of the fluid came back clear, without bacteria, viruses, or the cells and antibodies seen in rare autoimmune diseases. An EEG, which measures the electrical activity of the brain, showed no seizures or other abnormalities.

So what had turned this otherwise healthy child into Rip Van Winkle? We had spent hours on test after test, all of which were unrevealing. Her parents were bereft. I was hopeful that the tincture of time would provide more answers.

Body Disruption

Several hours later, with Maddie still sleeping silently, we got an answer. Her urine toxicology tests returned positive for only one substance: delta-9-tetrahydrocannabinol, better known as THC — the psychoactive ingredient in marijuana. Even though recreational and medical marijuana was legal in our state, Colorado, her parents were shocked, adamant the results were not possible.

“We never ever use pot,” both parents exclaimed. “We’ve never had any in our home. How is this possible?”

I considered the possibility of a false negative result, yet the few substances that do this are rare, prescribed medications, and unlikely for Maddie to be able access. Her symptoms fit too well with those associated with THC ingestion.

THC overdose in children — particularly when it’s taken in its edible form — can put them into a deep slumber, sometimes even a coma. Within an hour or two of ingesting it, young children under the age of 10 can become drowsy, clumsy, and out of balance. With larger doses, they become unresponsive. Meanwhile, the chemical compound itself settles into the body’s fat, lingering for days. While similar symptoms can be seen in adults, when children ingest an edible, the dosage is so large for their small bodies that they feel much more significant effects.

Specifically, THC impacts the body through cannabinoid receptors, scattered in the brain and nerves. These receptors form the endocannabinoid system, which acts as conductor for an orchestra of neurotransmitters, turning up or down the volume on sleep, temperature, pain, hunger, learning, and memory. In Maddie’s case, the THC she had eaten had disrupted her body’s sleep-wake cycle.

The next morning, Maddie finally woke up. Alert and very hungry, she was able to help us solve the mystery. “I met a new friend at the campground,” she told us. “She gave me a bunch of gummy bears. They were yummy but made me feel pretty weird.”

Maddie’s parents remembered the family at the neighboring campsite, who were friendly and had kids similar in age to Maddie and her sister. They never thought to worry the candy they shared would cause anything more than a sugar high. That night, Maddie had slept soundly on the car ride home, and her parents thought nothing of it; they had all hiked miles that day. It wasn’t until she wouldn’t wake the next morning that they realized something was wrong.

Practical Measures

Marijuana is legal for either medical or recreational use in nearly half the states in the U.S. As marijuana legalization has spread, however, so have pediatric THC overdoses. The drug is unusually appealing to children, as it often comes in edible forms that look just like regular sweets, such as cookies, brownies, chocolate, or gummies. It’s easy for even toddlers to unwittingly devour handfuls of these “special” treats. A study by Children’s Hospital Colorado and the Rocky Mountain Poison & Drug Safety Center found half of cannabis exposures in children under age 9 came from edibles.

What’s more, edible THC products are made with concentrated THC-infused oils, which can give a larger dose than in other forms of marijuana and last longer in the body. One cookie may contain five servings of THC.

In recent years, doctors and researchers have seen rates of THC ingestions in children skyrocket. In the U.S., reported cases of THC exposure in children under age 6 increased more than 1,000 percent between 2017 and 2021, from about 200 to more than 3,000, according to a 2023 study in the journal Pediatrics. The average age was 2 years old. A third of those children were treated, evaluated and released from the hospital, while 15 percent required admission and 8 percent were sent to the intensive care unit.

There’s no antidote for THC poisoning, no reversal agent, no special treatment. Care involves making sure nothing else is causing the child’s symptoms, helping them breathe if needed, and letting them sleep off their high. After they wake up, most children seem to be back to their normal selves, without any known later health consequences.

With practical measures and forethought, though, children can be kept safe from THC poisoning. Several states have passed laws requiring childproofing packaging for marijuana products. Caregivers should safely store marijuana in any form, keeping it locked and out of a child’s reach, while parents can make sure that marijuana also is kept out of reach in any other homes where their children spend time.

Thankfully, after a 16-hour sleep, Maddie was back to her chipper self, voraciously eating chips and a sandwich, eager to go home and take a shower after camping. Her parents, meanwhile, were relieved that their daughter awoke without any health problems. Still, they vowed that on their next camping trips, they would be much more vigilant about watching out for bears — real and gummy alike.

This story was originally published in our May June 2024 issue. Click here to subscribe to read more stories like this one.