Last updated : November 18, 2024
Is marijuana really a safe drug? The answer is a bit complicated. Currently, marijuana is labeled as a Schedule I drug in the U.S., which means that under federal law it is illegal and can’t be used for medical purposes. However, marijuana is now legal for specific medical purposes and even recreational use in some states.
Experts say much more study and information is needed to decide marijuana’s full impact on the body. Some studies show the drug seriously affects people’s behavior and has a major impact on society.
Margin of exposure
A comparative risk assessment of marijuana, conducted by Dirk Lachenmeier and Jurgen Rehm, was recently published in Scientific Reports. The two investigated the risk associated with a variety of substances using what’s called the ’margin of exposure’ approach. The MOE method looks at the amount of a drug a person would ‘normally’ take or consume in a day and compares it to the lethal dosage of that same drug. This is the MOE. Basically, the lower the MOE, the greater the likelihood an overdose of the drug would kill.
Marijuana’s MOE
The active ingredient in marijuana is tetrahydrocannabinol, or THC, and its MOE is on the high side, over 100, which means the chances of an overdose, a lethal one, are low. However, researchers warn there are several cautions regarding that MOE.
They point out these MOE findings were actually based on animal data, not humans. This is both unethical and misleading. Also in this study, the researchers tested drugs individually, while in reality, most people ‘mix’ several drugs at once.
Too narrowly focused
Many doctors and researchers warn that this study had too narrow of a focus. The study looked at acute toxicity only, which is just part of the analysis needed to decide a drug’s risk.
An MOE won’t factor in other health risks associated with marijuana, such as memory loss, impaired decision making and driving ability, drug dependence and so on. There is also new evidence which suggests marijuana may be associated with heart problems. According to a 2014 issue of Forensic Science International, two German men died after using marijuana.
While marijuana may be seen as having a low overdose risk, the effects of long-term use of the drug were not considered. Today, we know smoking cannabis increases the risk of lung disease while using marijuana in any form can cause dependence and mental health issues. Because of this, the true harm of using marijuana has been greatly underestimated by simply using the margin of exposure approach.
In 2014, the World Health Organization estimated the fatal dose of THC to be between 15 and 70 grams. While this is a much greater amount than a cannabis user would smoke in a day, research shows marijuana use doubles the risk of car accidents when driving under the influence and experiencing psychoses in adulthood. The WHO says that nearly one in 10 regular users develop dependence.
Children and marijuana
As most people might guess, the amount of marijuana an adult can safely ingest versus the amount a small child, or even a baby, can ingest safely are vastly different. In 2017, doctors reported the first ever death by marijuana overdose. An 11-month old baby boy was brought to the hospital by his guardian, reporting the baby had been retching and was irritable and despondent. His heart stopped, and doctors were unable to resuscitate him. After his death, doctors found his urine and blood to be full of THC.
When investigated, his living situation was found to be untenable, with both of his parents drug users. The doctors believe the baby ingested a large amount of marijuana in a short period of time.
A recent study done by a group of doctors led by Dr. Karen Wilson showed children absorb the chemicals in secondhand marijuana smoke. Their study tested children ages one month to two years who had been hospitalized for bronchitis; 75 percent of those whose caregivers admitted the children had been exposed to secondhand marijuana smoke tested positive for marijuana.
These doctors warn against smoking marijuana around kids, as the exposure is not safer than tobacco smoke exposure. “Our hypothesis is that it is not good for kids,” Dr. Wilson says. “We strongly believe that once we do the research to document secondhand marijuana exposure that we will see there is a negative effect on children.”
Teens and Marijuana Use
The number of teens using marijuana is on the rise, as is their admittance to the emergency room because of it. In Denver, a study by a doctor at Children’s Hospital Colorado shows that more and more teens and young adults are being admitted for what appear to be marijuana-related reasons.
Dr. Sam Wang, who conducted the study, found that 106 teens and young adults were admitted to the Children’s emergency room for marijuana-related reasons in 2005. In 2014, the number was 631. He also noted the number of teens and young adults in the emergency room for marijuana-related reasons and who then needed a psychiatric evaluation also increased. In 2005 that number was 65; in 2014, it was 442. Dr. Wang notes these patients generally receive psychiatric evaluations because they are also intoxicated at the time of admittance or may have tried to commit, or talked about committing, suicide.
So what’s the verdict?
While you probably won’t die from a marijuana overdose, a preponderance of evidence shows beyond a reasonable doubt that marijuana certainly is not a safe drug.