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Since feeling safe is a precondition for consenting to begin, and remaining in, treatment, this raises distinct ethical demands on care. Which features of the setting enable patients to feel safe, and how patients' and clinicians' understandings of the treatment relate to these requirements, remains unclear. This study identifies patient-, clinician- and setting-related factors shaping the experience of safety during (es)ketamine treatment and derives ethically grounded recommendations, distinguishing clinical safety, felt safety and ethical protection and analyzing their relations through a framework of induced, layered vulnerability.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Semi-structured interviews were conducted with 14 patients who had received intranasal esketamine (Spravato\u00ae) or IV ketamine infusion treatment and 10 clinicians administering these treatments in German psychiatric settings, and analyzed using structuring qualitative content analysis complemented by type-building analysis. Pre-treatment concerns and the experience of safety were analyzed from the patient interviews; clinician interviews informed the broad coding and the comparison of patients' and clinicians' models of ketamine's mechanism of action.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Three types of pre-treatment concern, three overlapping modes of experiencing safety, and three models of ketamine's mechanism of action were identified, each associated with distinct treatment requirements. Therapeutic presence, active physical grounding, and structured post-acute transitional support (\u201clanding aid\u201d) were described by participants as central to feeling safe. Clinicians more often conceived of ketamine as a catalyst of transformation, patients as temporary relief or symptom management, indicating potential misalignment regarding preparation and integration.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Safety in (es)ketamine treatment is relationally created and individually differentiated rather than uniform, supporting an ethical case for flexible, patient-centered care above a non-negotiable floor of clinical safety. Because patients in altered states depend acutely on those who induced that state, minor clinician behaviors and the post-acute transition carry moral weight bearing on informed consent and the duty of care, yet are modifiable with few resources. Recommendations are graded by strength; one is restricted against our own empirical finding where the vulnerability analysis requires it. As an exploratory study, the findings require confirmation in larger, more diverse samples.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12910-026-01637-7","type":"journal-article","created":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T14:25:00Z","timestamp":1791469500000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Feeling safe: an empirical-ethical analysis of vulnerability in (es)ketamine treatment"],"prefix":"10.1186","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5798-8513","authenticated-orcid":false,"given":"Adrian","family":"Kind","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-7964-3752","authenticated-orcid":false,"given":"Josephine","family":"G\u00f6rke","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-9163-4926","authenticated-orcid":false,"given":"Hannah","family":"Smirr","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-2775-1317","authenticated-orcid":false,"given":"Christina","family":"Ni","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2788-8420","authenticated-orcid":false,"given":"Karen","family":"Yan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5130-6286","authenticated-orcid":false,"given":"Dimitris","family":"Repantis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,10,8]]},"reference":[{"issue":"7","key":"1637_CR1","doi-asserted-by":"publisher","first-page":"695","DOI":"10.1176\/appi.ajp.2017.17010098","volume":"174","author":"ST Wilkinson","year":"2017","unstructured":"Wilkinson ST, Toprak M, Turner MS, Levine SP, Katz RB, Sanacora G. 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