The world's first documented fatal marijuana overdose has been reported for the first time by two doctors in Colorado.

An 11-month-old boy died of a sudden heart attack that the doctors claim was caused by high levels of marijuana in his system.

He was brought to the Rocky Mountain Poison and Drug Center, where Dr Thomas Knappe and Dr Christopher Hoyte could find nothing to explain his heart inflammation, aside from his levels of THC - the psychoactive component of marijuana, reports Daily Mail.

The case, originally published in a journal in August, has ignited debates over both the risks of marijuana and the legitimacy of the doctors' claims since they came forward today.

Advertisement

According to the original case study, the boy had been living in an 'unstable' situation in a hotel, but had previously been healthy, and appeared well-fed to the doctors.

But that morning he was reportedly sluggish before having a seizure. After recovering he tried to vomit, and eventually lost consciousness.

When he arrived at the emergency department of the University of Colorado Colorado of medicine at Anschutz Medical Center in Aurora, Colorado, the infant was completely unresponsive, slipped into a coma and then had a heart attack.

Despite an hour's worth of attempts to revive him, the little boy died at the hospital.
The doctors performed an autopsy, but claim that they could find no signs of infection, and nothing unusual to explain the heart inflammation that had killed him.

With one exception: His blood work revealed that he had 7.8 nanograms/ml of THC - the active ingredient in marijuana - in his blood.

THC causes the sensation of a "high," and is often excluded from medical marijuana which uses cannabidiol (CBD) to relax muscles without the psychoactive effects.

In Colorado, an adult is considered to be driving illegally under the influence if they have more than five nanograms of active THC in their blood.

It is unclear how exactly the infant came to have such high levels of THC in his blood, but his parents admitted that they had marijuana in some form in their household. Photo / 123RF
It is unclear how exactly the infant came to have such high levels of THC in his blood, but his parents admitted that they had marijuana in some form in their household. Photo / 123RF

The doctors were unable to determine how the boy had gotten exposed to so much of the psychoactive chemical.

According to their report, the parents were unsure if he had eaten an edible, or ingested the cannabis some other way, but admitted to having drugs - including marijuana - in their household.

The claims of critics and anti-drug campaigns that weed can kill have long been debunked and even organizations like the National Institutes of Health and CDC acknowledge that there have been no previously documented cases of overdose.

But if the doctors' conclusions are confirmed, this boy's sudden death could drive new challenges to marijuana legalization and research efforts.

Much of the research done on cannabis and heart attacks, heart disease and stroke is based on people who were either also taking other substances, or had smoked marijuana.

Since smoke inhalation has known effects on heart health, it's difficult to establish to what extent these health problems are caused by the smoke or by the cannabis itself.

Marijuana-smoking has been shown to aggravate chest pain for those who already have heart problems, but, that is "one of the few things scientists know for sure about marijuana and cardiovascular health," according to a Harvard University explainer on the subject.

Aside from people with heart disease, inexperienced cannabis users are the most likely to feel the effects of the substance on their hearts. Marijuana has been shown to drive heart rates and make the heart work harder, especially in new users.

But no deaths have ever been reported as directly caused by the drug.

This case study is also unique in that it involves a child. There is, of course, little research dedicated to cannabis's effects on people under 18.

Hospitals have seen an increasing number of children coming to the ER after cannabis exposure, according to recent research. Marijuana was legalized in Colorado in 2012. A study published in JAMA reported that marijuana cases for children under 10 increased by 34 percent in Colorado between 2009 and 2015.

While no one has been able to previously prove that cannabis was the cause of a death, a robust body of research has documented the therapeutic benefits of the previously reviled drug for cancer patients, a non- (or less, depending on what you read) addictive alternative painkiller to opioids.

It is also worth noting that most sudden cardiac arrests in children happen before they reach their first birthdays - as it did for the boy in the case study.

Often they are caused by respiratory failure, but many are categorized as incidents of sudden infant death syndrome, and have no clear explanation.