Subjective responses to psychedelic drugs, such as mystical experiences and oceanic boundlessness, often correlate with therapeutic improvements in conditions like treatment-resistant depression, end-of-life anxiety, and substance use disorders. Measuring these responses is challenging; several scales show good reliability and factor structure, but samples are often small and self-selected. This review examines the psychometric properties of widely used scales and their links to treatment outcomes. Challenging experiences, psychological insight, and emotional breakthroughs also show promise, though replication is needed. A collaborative approach to data collection on subjective reactions in therapeutic settings could help predict improvement across conditions.
Among 228 healthcare providers who treat psychiatric disorders with medications and reported at least one lifetime psychedelic use, retrospective measures showed improvements in depression, anxiety, and well-being after psychedelic exposure. Suicidality decreased and resilience increased. A factor analysis indicated that a cluster of mystical, interpersonal, and personal experiences predicted these improvements. The preferred psychedelic agent did not affect outcomes, and frequency of use was not associated with outcomes, though effect sizes varied. Harm was reported by 13.2% (n = 30), consistent with general population rates. Pre-exposure alcohol use, aggressive impulses, and desire to die by suicide improved most often, while marijuana use most often worsened or did not change.