Persistent Altered States: Psychological Treatment of Psychedelic Adverse Effects

Interest and use of psychedelic substances is on the rise in the general population. Research has mainly focused on therapeutic applications in formal treatment settings, and little is known about persistent negative effects in naturalistic use. The aim of this paper is to present a clinically relevant overview of the phenomenology and symptoms of enduring mental health problems after psychedelic use. Three central domains of post-psychedelic difficulties are presented, informed by clinical work on this subgroup and a narrative literature review: (a) anxiety and feelings of unreality, (b) persistent changes in perception, and (c) existential distress. These are broad groupings and intended as suggestive rather than authoritative on the breadth and nature of complications after recreational psychedelic use. Challenges and recommendations for psychotherapeutic work with this subgroup is discussed in the context of principles for evidence-based practice. Keywords: psychedelics, negative effects, adverse reactions, HPPD, existential distress