Synthetic cannabinoids have been found to exhibit greater affinity to CB1R than THC and greater affinity to CB1R than to CB2R; pharmacologically, a series of in vivo and in vitro studies has shown that they are 2–100 times more potent than THC [31] and that they exert THC-like physiological and psychotropic effects [32], but with remarkable potency and efficacy, which often result in serious adverse effects that require medical attention, including psychiatric, cardiovascular, and gastrointestinal sequelae [33]; psychosis, paranoia, anxiety, and confusion [34,35]; and even death [36]. This evidence concerns the gene CNR1 and Anxiety.