Abstract
Background/Objectives: Esketamine-related dissociation is a transient, pharmacologically induced altered state that differs from the trait-like pathological dissociation typically observed in trauma-related conditions. While most studies have quantified these effects using the Clinician-Administered Dissociative States Scale (CADSS), patients' subjective phenomenology and meaning-making remain underexplored. This qualitative exploratory study investigated how patients narrate, interpret, and integrate dissociative experiences occurring during intranasal esketamine treatment for treatment-resistant depression (TRD). Methods: We conducted semi-structured interviews with 36 adults with TRD who were receiving intranasal esketamine in outpatient settings in Northern Italy (2022-2024). Interviews focused on the most salient dissociative experiences during treatment. Transcripts were anonymized and analyzed using inductive thematic analysis. Two researchers coded the data independently; discrepancies were resolved by consensus, and recruitment continued until thematic saturation was reached. Results: Four experiential domains emerged: sensory alteration and perceptual flow (10/36, 27.8%), time suspension and chronological drift (21/36, 58.3%), body and space alteration (20/36, 55.6%), and psychic distance from suffering (30/36, 83.3%). While a minority described transient distress or loss of control, most narratives framed dissociation as neutral or subjectively meaningful, often associated with a temporary reduction in ruminative self-focus and depressive distress. Conclusions: A narrative, phenomenological lens complements quantitative research by clarifying what esketamine-induced dissociation feels like to patients and how it is appraised in context. The findings do not imply a causal or mediating role in antidepressant efficacy. Rather, they suggest that dissociation functions as a transitional subjective state, the clinical relevance of which depends on anticipation, framing, monitoring, and integration. These results support the use of structured psychoeducation, in-session support, and post-session integration within real-world esketamine programs.