This short study investigated the question, whether the experimental data presented in a study by
Merrick and colleagues (2016) are of clinical relevance. These authors found that cannabidiol (CBD),
a major cannabinoid of the cannabis plant devoid of psychotropic effects and of great interest for
therapeutic use in several medical conditions, may be converted in gastric fluid into the psychoactive
cannabinoids delta-8-THC and delta-9-THC to a relevant degree. They concluded that “the acidic
environment during normal gastrointestinal transit can expose orally CBD-treated patients to levels
of THC and other psychoactive cannabinoids that may exceed the threshold for a positive
physiological response.” They issued a warning concerning oral use of CBD and recommend the
development of other delivery methods.
However, the available clinical data do not support this conclusion and recommendation, since even
high doses of oral CBD do not cause psychological, psychomotor, cognitive or physical effects that
are characteristic for THC or cannabis rich in THC. On the contrary, in the past decades and by
several groups high doses of oral CBD were consistently shown to cause opposite effects to those of
THC in clinical studies. Thus, there is no reason to avoid oral use of CBD, which has been
demonstrated to be a safe means of administration of CBD, even at very high doses.