Update on the Neuropsychiatry of Substance Use Disorders.

This article reviews some of the recent discoveries about how neurobiological processes contribute to the understanding and treatment of substance use disorders. Particular focus is given to cannabis, opioids, and designer drugs. Important areas addressed include triggers and cravings, the central roles of dopamine and stress, and the endocannabinoid system. Clinical relevance of these findings for withdrawal management and relapse prevention is discussed. Also highlighted are issues related to the opioid epidemic and consequences both of continuing federal prohibition of cannabis as well as its state-by-state relaxation.