Adolescence is a critical period for suicidal risk. Suicide currently ranks as the second or third leading cause of mortality among adolescents in developped countries. It has been shown that a history of suicidal act, of depressive disorder and of a substance use disorder (SUD), alcohol and drugs, are the most prominent risk factors for suicidal behaviour among adolescents.

Data on alcohol and drug use disorders and suicide consisted primarily of reports on alcohol use disorders and, to a lesser extent, opioid use disorder. The magnitude of the association with other drugs is still unclear.

The relationships between substance use disorder and suicidal behaviour are multiple: In the long term, SUD may be associated with increases in stress and co-occuring psychopathology (poor self esteem, feeling of worthlessness, isolation).These elements may reach a level where a suicide attempt is viewed as a means to cope with perceived unsolvable difficulties. During life crises, SUD can also be responsible for inhibiting adaptative coping and desinhibiting suicidal behaviour. Finally, SUD and suicidal behaviour share common vulnerability factors: history of childhood abuse, genetically determined dimensions such as impulsivity or psychiatric disorders, particularly unipolar depressive and bipolar disorder.

Given the comorbidity between SUD and suicide, it is essential for treatment and prevention that all suicidal adolescents be screened for SUD and vice versa. Ideally, adolescents who receive diagnosis of SUD and co-occuring suicidality should follow an integrated treatment protocol that addresses both conditions.