Obsessive-compulsive disorder, major depressive disorder, and addiction: the vicious relationship.

Obsessive-Compulsive Disorder (OCD) and Major Depressive Disorder (MDD) are prevalent psychiatric conditions, each affecting a substantial portion of the global population. When these conditions coexist with a Substance Use Disorder (SUD), the complexity of the clinical presentation is heightened. Herein, we describe two cases of individuals who have comorbid OCD and/or MDD and substance use disorder that highlight the importance of addressing the coexisting psychiatric illness when treating the SUD. These cases highlight the importance of tailored, multidisciplinary care, offering a potential therapeutic strategy based on medications for comprehensive recovery in individuals facing complex comorbid disorders. An integrated treatment approach, encompassing both psychiatric and substance treatment perspectives, is imperative.