Cannabis use in early adulthood is prospectively associated with prescriptions of antipsychotics, mood stabilizers and antidepressants.

Cannabis is an acknowledged risk factor for some mental disorders, but for others the evidence is inconclusive. Prescribed medicinal drugs can be used as proxies for mental disorders. In this study, we investigate how use of cannabis is prospectively related to prescription of antipsychotics, mood stabilizers, antidepressants and anxiolytics.Data on cannabis exposure and relevant confounders were obtained from 2,602 individuals in the longitudinal Young in Norway Study, providing survey data from four data collection waves between 1992 and 2006. Data were coupled with information about prescriptions for psychotropic drugs from the Norwegian Prescription Database between 2007 and 2015.Past year cannabis use increased the risk of prescription of antipsychotics (OR = 5.56, 95 % CI 1.64 - 18.87), mood-stabilizers (OR = 5.36, 95 % CI 1.99 - 14.44) and antidepressants (OR = 2.10, 95 % CI 1.36 - 3.25), after accounting for socio-demographic variables, conduct problems, additional drug use, mental distress and prescriptions the year before cannabis use was measured.In this study of young adults from the general population, past year cannabis use was associated with later prescriptions of antipsychotics, mood-stabilizers and antidepressants.