Psychedelic experiences produced both more positive and more negative effects than cannabis experiences

Psychedelic experiences had greater acute challenging effects and persisting negative effects compared to cannabis, but also greater positive acute and persisting effects. Common predictors of outcomes included dose level, presence of others, religiosity, and personality traits, though these explained only small amounts of variance.

Two studies using opt-in panel sampling reflecting US Census demographics: a between-subjects design (n=743) comparing psychedelic vs cannabis experiences, and a within-subjects design (n=514) in dual-experienced users.

As psychedelics gain therapeutic attention, comparing their risk-benefit profile to the most commonly used illicit substance provides practical context. Cannabis serves as a useful benchmark because most adults have some reference point for it.

The finding that psychedelics amplify both positive and negative experiences compared to cannabis challenges simple narratives about either substance. It suggests psychedelics are not simply "more dangerous" or "more therapeutic" but operate at a higher intensity on both axes.

Retrospective self-report of first or most memorable experiences is subject to recall bias and narrative construction. Panel sampling, while better than social media convenience sampling, may not reach the most marginalized users.