Bipolar Patients Who Stopped Cannabis During a Manic Episode Had Similar Outcomes to Those Who Never Used

Data came from the European Mania in Bipolar Longitudinal Evaluation of Medication (EMBLEM), a 2-year prospective observational study across multiple European sites. Cannabis use was assessed between the 12-week and 24-month visits. Outcomes were analyzed using regression models controlling for confounding variables.

For people with bipolar disorder who use cannabis, this study provides evidence that quitting during a manic episode may lead to outcomes comparable to those who never used. It also reinforces that continued cannabis use during bipolar episodes is associated with measurably worse clinical trajectories.

The relationship between cannabis and bipolar disorder is complex. While some patients report symptom relief from cannabis, this longitudinal data suggests that continued use during manic episodes is associated with worse long-term outcomes, and that stopping use can meaningfully improve the trajectory.

This was an observational study, so the association between cannabis cessation and better outcomes could reflect other differences between the groups. Patients who quit may have had less severe illness or better treatment adherence overall. Self-reported cannabis use may be inaccurate. The relatively small proportion of cannabis users limits statistical power.