Co-occurrence of depression and a substance use disorder (SUD) in patients who present dual diagnoses has been long recognized as an important consideration in clinical practice. This review synthesizes the evidence of pharmacological and psychosocial interventions for comorbid depressive disorders and SUDs while providing clinical recommendations about the best interventions to address these patients. The best evidence from randomized controlled trials was used to evaluate treatment options. The strength of recommendations was described using the GRADE approach.

Our results suggest that 1) In patients with depression and alcohol consumption, the administration of non-selective serotonin reuptake inhibitor (SSRI) antidepressants instead of SSRI is recommended for improvement of depressive symptoms (strong recommendation). Neither SSRI (strong recommendation) nor non-SSRI (weak recommendation) antidepressants are recommended for reduction in alcohol consumption. 2) In patients with depression and cannabis use, the use of venlafaxine is not recommended (weak recommendation). 3) In patients with depression and cocaine consumption, the use of SSRI antidepressants for improving depressive symptoms (weak recommendation) or to reduce cocaine use is not recommended (strong recommendation). The use of non-SSRI antidepressants is only recommended for improving depressive symptoms (strong recommendation). 4) The administration of bupropion to reduce nicotine consumption is not recommended (strong recommendation). 5) Regarding psychological treatment, in patients with depression and co-occurring alcohol disorder, both pharmacotherapy and cognitive behavioural therapy have positive effects on internalizing symptoms and in reducing alcohol consumption (weak recommendation). Our review suggests the need for more research in this area and for larger, multisite, randomized studies to provide more definite evidence.