It’s a common story among cannabis users—that time they consumed a higher dose than they intended or simply became too intoxicated, turning a recreational or medicinal experience into something unpleasant. While each story is different, often, the commonality is the mode of ingestion: edibles. Unfortunately, this is often why edibles often get a bad name.
Many who find themselves in this situation, knowing that cannabis has never caused any deaths, usually understand they must “ride” out these effects by giving the cannabinoid levels in their body some time to dissipate. However, those either new to cannabis or perhaps not familiar with edibles may find the effects too overwhelming to manage alone, causing them to seek medical help.
Healthcare professionals in Colorado, where cannabis use has been fully legalized since 2012, are well aware of this situation.
A study published in the Annals of Internal Medicine recently looked at this issue. Andrew Monte, MD, and others reviewed charts of emergency room (ER) visits from January 2012 to December 2016 to better understand how many people were seeking treatment due to cannabis. Overall, there was a 3-fold increase in cannabis-related ER visits over the time period. They also found that nearly 10% of visits attributable to cannabis use were due to edibles with the vast majority due to cannabis inhalation. [1,2]
While edible ingestion resulted in far fewer visits overall, it’s important to note that edibles accounted for a very small percentage of sales in Colorado during that time period (less than 0.5% based on kg of THC according to the study), which puts that 10% in perspective. 
Patients included in this observational study who had consumed edibles reported greater intoxication, acute psychiatric and cardiovascular symptoms compared to those who had been exposed via inhalation, who reported more gastrointestinal symptoms. This study did not report the dosages consumed nor did they specify the formulation (THC:CBD ratio, etc.). 
While it’s clearly possible to become too intoxicated after inhaling cannabis or ingesting edibles, why is it that edibles cause different symptoms?
When consumed in a food like a gummy or brownie, cannabinoids are first exposed to the body in the gut, where they are broken down and then slowly absorbed via the intestines. This process takes longer than inhaling cannabis, which is why the effects of edibles take much more time to fully kick in and why those effects last so long. 
To make matters a bit more complicated, pharmacodynamics (or how drugs move through the body) is impacted by many factors, including the amount and types of food consumed that day (especially since cannabinoids are lipophilic, or fat-loving), hydration level, height, weight, and other substances also in the body like medications.  These factors combined with differences in metabolism can often lead to varied responses to cannabis, especially when taken in the form of edibles.
What can be done to prevent this unpleasant experience?
Some methods have been proposed colloquially to mitigate these effects, although they have not been scientifically proven. One method is to consume terpenes that may help induce calm; an example is to eat black pepper, which contains beta-caryophyllene.  Another is to consume CBD to counter the effects of high levels of THC, but some folks say that’s a misconception Again, none of these have been scientifically evaluated.
It’s important to remember that, in the described study, the vast majority of ER visits were due to cannabis inhalation, not edibles. So it’s essential to pay attention to how different cannabinoids, formulations, and doses may affect the cannabis experience—not just edibles.
Until we better understand exactly how cannabis should be dosed (a very hot topic in research), cannabis use should be tailored individually—and this may mean some trial and error. For now, the old age of “start low, go slow” seems to be the best way to determine the optimal dose for any type of cannabis ingestion method, whether for recreational or medicinal use.
Photo credit: SELF
- Monte, A.A., et al. “Acute Illness Associated with Cannabis Use, by Route of Exposure: An Observational Study.” Ann Intern Med. vol.170, no.8, 2019, pp. 531-537. (impact factor: 19.315; cited by: 15)
- Volkow, N.D. & Baler, R. “Emergency Department Visits From Edible Versus Inhalable Cannabis.” Ann Intern Med. vol.170, no.8, 2019, pp. 569-570. (impact factor: 19.315; cited by: 1)
- Russo, E.B. “Taming THC: Potential Cannabis Synergy And Phytocannabinoid-terpenoid Entourage Effects.” Br Pharmacol. vol.163, no.7, 2011, pp. 1344-1364. (impact factor: 6.81; cited by: 624)