Addiction cannot be studied or discussed without fully understanding the role that psychological disorders and mental illness play in the onset of addiction, the course of the disease, and the outcome of treatment. Specifically, it is important to understand how depression is interrelated with addiction. It must be understood how the interplay of all aspects of both disorders affects the outcome of both. It is not enough to simply understand that there may be a genetic link between the two disorders. Depression can be both a cause of, and an outcome of, addiction. It will impact the path taken by those who suffer from substance use disorders (SUDs). Therefore, it is necessary to understand the complexity of the relationship between the two disorders. Whether depression ...