Synthetic cannabinoids are one of the most rapidly expanding classes of novel psychoactive substances found in illegal markets. These substances have evolved to the point that many examples no longer fit with the traditional cannabinoid classification system, where assignment of these compounds is difficult and ambiguous, leading to inconsistencies in regard to their chemical structures. This and other drawbacks can result in misunderstandings between forensic scientists and legal disciplines, complicating efforts toward improving the inadequacies of current antidrug laws. After a critical review, we offer an updated yet simplified cannabinoid classification system with the intention to facilitate interdisciplinary communication.
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