One of the biggest controversies in the cannabis field is whether CBD alters the physiological effects of THC. Many believe that CBD offsets some of the adverse effects of THC thereby making it more tolerable. And for sure, a number of studies have pointed towards such a possibility, especially where the ratio if CBD to THC is high. Consequently, many believe that some of the adverse effects of THC can be “tamed” by adding CBD. While such a relationship can influence standards for safe THC limits, every effort needs to be made to ensure that such claims are substantiated.
In a study that was published in Neuropsychopharmacology in November 2022 researchers did not find any evidence that CBD prevents adverse effects that may be caused by THC. This led them to propose that the finding be considered in health policy decisions on medical and recreational cannabis.
This double blind crossover trial testing different THC: CBD rations asked the question, Does cannabidiol make cannabis safer? The study had 46 healthy participants who were infrequent users of cannabis. The participants were offered vaporized cannabis with different concentrations of THC and CBD in four visits. The ratios offered were 1:1, 1:2, and 1:3 in a randomized and counterbalanced order. Even at a ratio of 3:1, CBD neither altered the subjective pleasurable effects of THC nor did it reduce adverse effects. This led the researchers to rule out CBD as a critical consideration in defining a standard THC unit as well as determining the safety of a cannabis product.
Can Higher CBD: THC Ratios Change How THC Feels?
While CBD may not alter how THC feels at a ratio of 3:1, higher ratios exceeding 10:1 may indeed do so. Though CBD and THC both have action on the CB1 receptor, their mechanism of action is quite different. CBD has an open and twisted ring which does not allow it to fit well into the orthostatic CB1 receptor. Therefore, CBD modulates the CB1 receptor from allosteric sites. THC on the other hand binds directly to the orthostatic sites on the CB1 receptors. This suggests that CBD can trigger biased CB1 agonism and this can affect the downstream effects of THC. Indeed, preliminary reports with higher CBD: THC ratios have shown that CBD can taper off the adverse effects of THC. However, researchers in the study mentioned above have argued that this is not the effect of THC but rather it is the fact that the amount of THC in higher rations is not significant enough to cause adverse effects. Clearly, further studies are needed to provide direction on whether CBD makes THC safer.