There is a need to bridge the gap between the fields of addiction psychiatry and general psychiatry to effectively treat co-morbid substance abuse and psychiatric disorders. This alarming epidemic transcends communities and severely impacts healthcare worldwide, yielding poor treatment outcomes and prognoses for afflicted patients. Because substance abuse can exacerbate or trigger psychosis and mood disorders, it is important to keep these issues in the forefront when evaluating patients. To address some of the complications stemming from not enough interactions between various groups of practitioners, this review addresses the neurobehavioral effects of cannabis use and their impact on patients who suffer from psychotic or affective disorders. The hope is that this article will serve as a spring board for further discussions among practitioners who treat these patients. Greater interactions between caretakers are bound to impact the care of our patients in a very positive way.