appear to show a more consistent, beneficial effect in ameliorating mood under different conditions, which could present some promise for future use in mood-related disorders. Most studies from cannabis abusers have shown that high concentrations of THC and high ratios of THC:CBD were associated with more vigorous euphoria, but also with higher anxiety, depression and psychotic symptoms. It has also been shown that CBD attenuates some effects of THC such as anxiety, cognitive deficits, and psychosis in heavy cannabis users, and high CBD:THC ratios produce an effect opposite to the high THC:CBD concentrations [11,145,175,178,222,223,224,225,226]. However, the mechanisms by which CBD and THC interact or alleviate negative consequences are not clear, due in part to the multiple biological targets that both compounds can modulate. There is an undeniable need to identify the roles of these targets of THC and CBD, including different receptor complexes to clarify the different, and in some cases, opposite biological effects on the brain. This is particularly important with the view of identifying novel therapeutic targets for multiple illnesses, including anxiety and depression, using cannabinoid preparations devoid of side effects apparent during chronic treatment, including after the use of very low dosages [227], as well as to
