One of the main draws to using CBD oil in recent years has been the reputation of how safe it is. In fact, in 2017, the World Health Organization’s Expert Committee on Drug Dependence suggested that in addition to being “generally well tolerated with a good safety profile,” CBD had “no public health problems” when taken as a pure extract from the cannabis plant (including both hemp and marijuana varieties).
However, if you know your chemistry and/or toxicology, you’ll know that ALL chemical substances are potentially lethal if taken in a high enough dose. Even water can be fatal to humans if too much is consumed within too short a time period.
Moreover, given the fact that Epidiolex (a CBD-based epilepsy drug) just became the first ever natural cannabis medicine to gain FDA approval, more and more individuals are curious as to what the toxicity level of CBD oil is. In other words, how much CBD oil would it take to kill you?
In this article, we aim to answer exactly that question.
First Things First: What is Toxicity?
In general, the FDA requires that all approved medicines have an established toxicity level, or what’s known as an LD50.
The LD50 (LD stands for “lethal dose”) of any given chemical compound is the amount that it would take to kill 50% of test subjects at a certain dose. The “test subjects” are typically female rats (according to the FDA females are more sensitive to toxic effects than males), though any animal species could hypothetically be used.
For instance, if 100 rats were given 1,000 mg of ibuprofen and the dose proved to be lethal for 50 of them, we could accurately say that the LD50 for ibuprofen was 1,000 mg (this is a very loose generalization, and is not the actual LD50 for ibuprofen).
To be clear, clinical trials for an FDA-approved medicine do not have to disclose an LD50 for the drug in question. There simply has to be clear pre-existing scientific evidence that establishes some form of toxicity for the compound.
As such, the recent approval of Epidiolex did not disclose a specific LD50 or a human toxicity level for CBD oil. However, multiple previous studies have attempted to determine such a level for both cannabidiol (CBD) and 9-tetrahydrocannabinol (THC).
How Much CBD Would it Take to Kill You?
The toxicity levels for CBD (otherwise known as cannabidiol, which is the active ingredient in Epidiolex) are, in fact, listed by the federal government’s Toxicology Data Network. Three separate LD50’s have been determined from three different studies, spanning more than 70 years:
- In 1946, the LD50 for cannabidiol in dogs was determined to be greater than 254 mg per kg of body weight, when administered intravenously.
- In 1975, an LD50 was established in mice at 50mg per kg of body weight, when administered intravenously.
- In 1981, a report in Toxicology and Applied Pharmaocology show the LD50 for CBD to be 212 mg per kg of body weight when administered intravenously in monkeys.
More recently, a 2011 article in Current Drug Safety observed toxic levels of CBD in rhesus monkeys when administered orally. Doses over 200 mg per kg of body weight proved to be fatal in some monkeys by way of respiratory arrest and cardiac failure, while 300 mg per kg of body weight resulted in “rapid death.”
For reference, consider a relatively “average sized” human at 75 kg (approx. 165 lbs). By these numbers, it would take roughly 18,750 mg (18.75 g) of CBD consumed within a very short amount of time to result in any potentially fatal effects. By comparison, most typical CBD oil users consume no more than 100 mg of the compound — and that’s throughout the course of an entire day.
Other Interesting Facts on Cannabis Toxicology
Perhaps even more interesting than these figures are the toxicology figures that have been determined (or have tried to be determined) for other natural cannabis compounds – including whole plant marijuana.
In one 2018 report in Toxicology Communications, an LD50 for “crude marijuana extract” in beagles (a species of dog) could not even be determined as doses greater than 3,000 mg per kg of body weight did not result in any fatalities.
The same was true for rhesus monkeys, wherein a dose of 5,000 mg per kg of body weight “failed to elicit any sign of toxicity.” Moreover, doses of up to 9,000 mg per kg of body weight in primates had “no significant toxicity effects.”
According to these figures, the report concluded an “estimated” LD50 for marijuana extract to be larger than 10,000 mg per kg of body weight in primates.
Finally, in a 2016 report prepared for the FDA’s “8-Factor Analysis on Cannabis,” the research organization Americans for Safe Access (ASA) claimed that there is currently no known LD50 for any form of cannabis in humans – including any of its major component extracts.
The report emphasized the fact that researchers have for years been attempting to determine a consistent LD50 rating for cannabis in animals, with unsuccessful results. One statement in the report claimed that “researchers have continuously been unable to give animals enough natural Cannabis to induce a death.”
By current ASA estimations, in fact, a marijuana smoker would have to consume 20,000 to 40,000 times the amount of cannabis contained in a standard marijuana cigarette (defined by the National Institute on Drug Abuse to be 0.9 g) in order to experience any potentially fatal consequences. For reference, this would be approximately 1,500 lbs of cannabis within a 15 minute period to induce a “theoretically lethal response.”
By comparison, it’s common knowledge that the nicotine content in a single pack of tobacco cigarettes is enough to kill most humans, if ingested all at once.
Final Thoughts on CBD Oil Toxicity Levels
To be clear, there is no exact “lethal dose” of CBD oil in human beings. By and large, the compound is an incredibly safe, well-tolerated, and non-addictive substance that has profound therapeutic effects on a wide variety of physiological conditions.
In one study on human epilepsy patients, for example, no signs of “toxicity or serious side effects” were detected from the use of CBD, even after daily 200-300 mg doses for 135 days. In order to gauge any potential negative effects of the compound over the course of the study, neurological and physical examinations were conducted at weekly intervals, as were blood and urine analyses, EKG tests, and EEG studies – all of which came back standard.
Based on the above data, it is clear beyond the shadow of a doubt that CBD – and in fact all forms of cannabis – should be legalized across the U.S. in order for more patients to gain access to its medicinal and therapeutic effects.