Psychedelic-assisted psychotherapy: Where is the psychotherapy research?

High-dose administration of classic psychedelics paired with psychotherapeutic support before, during, and after dosing sessions is increasingly being studied as a potential treatment for several psychiatric conditions. Aday and colleagues describe two principal rationales for combining drug and psychotherapy: safety (therapeutic support is thought to reduce the acute risks of giving a psychedelic) and efficacy (psychedelics may transiently relax prior beliefs, increase suggestibility, and promote neuroplasticity in ways that could augment psychotherapeutic processes). The authors emphasise that this context sensitivity makes it important to understand which psychotherapeutic elements are necessary or sufficient for clinical benefit. The paper sets out to review the current status of psychotherapy within psychedelic-assisted psychotherapy (PAP), summarising psychotherapeutic models used in published clinical trials and putative models proposed in the literature. It also aims to draw lessons from decades of traditional psychotherapy research about standardising treatments, identifying mechanisms of change, and optimising trial design, with the overarching goal of highlighting gaps and priorities for empirical study of the psychotherapeutic component of PAP.

Aday and colleagues present a narrative, conceptual review rather than a formal systematic review or meta-analysis. The authors synthesise existing clinical trial reports, historical models from mid-twentieth century research (for example psychedelic peak therapy and psycholytic approaches), contemporary trial practices, and theoretical proposals about mechanisms and therapy modalities that might be synergistic with psychedelics. They also draw on methodological literature from traditional psychotherapy research to suggest study designs and standards that could be applied to PAP. The extracted text does not report a specific search strategy, databases searched, inclusion/exclusion criteria, dates of coverage, or a formal risk-of-bias assessment for included trials. Instead, the paper organises material thematically across topics such as current PAP practice (preparation, dosing, integration), varieties of psychotherapeutic approaches used or proposed, putative mechanisms of change, issues with treatment description and standardisation, and methodological tools from psychotherapy research (for example dismantling studies, comparative efficacy trials, and cross-lagged panel models). The authors integrate examples from individual trials where relevant, and discuss empirical gaps and design considerations for future research.

The review finds that contemporary PAP trials commonly follow a three-stage sequence: preparation (psychoeducation, expectation-setting, goal identification, establishment of therapeutic relationship), dosing (typically multi-hour sessions in a controlled environment with music and therapist support), and integration (sessions aimed at meaning-making and applying insights to daily life). Modern trials are heavily influenced by the psychedelic peak therapy model, which uses high doses to induce transformative states and typically adopts a non-directive, supportive stance during dosing. Mid-twentieth-century variants such as psycholytic therapy (lower doses combined with ongoing psychotherapy) have been largely sidelined in contemporary protocols. A wide range of psychotherapeutic modalities have been used or proposed alongside psychedelics, including cognitive behavioural therapy (CBT), CBT combined with motivational interviewing, Acceptance and Commitment Therapy (ACT), Internal Family Systems Therapy, EMDR, existential and psychodynamic approaches, mindfulness, psychoanalysis, group therapy, virtual reality adjuncts, and common-factors or novel therapies. The authors report that putative mechanisms of change identified in PAP work include awe, mystical-type experiences, increased acceptance, reduced rumination, greater cognitive flexibility, and therapeutic alliance, but empirical measurement of many of these constructs has been limited. A key empirical finding highlighted by the authors is the scarcity of trials that manipulate the psychotherapeutic component. The only trial noted to directly vary aspects of psychotherapeutic support randomised 75 healthy participants into three groups: very low-dose with standard support (LD-SS), high-dose with standard support (HD-SS), and high-dose with high support for spiritual practice (HD-HS). At six months, both high-dose groups showed large positive changes on measures such as interpersonal closeness, gratitude, meaning/purpose, and spiritual/religious measures compared with LD-SS. Differences between the two high-dose groups were generally small, suggesting dose had a larger impact than the manipulated contextual support in that study. The review documents shortcomings in treatment reporting: psychotherapy content and intensity are often minimised in methods sections, manuals are infrequently published, and provider eligibility (training, licensure) is not consistently defined. Mechanism measurement is also uneven: expectations are rarely measured despite being considered important, therapeutic alliance is predictive of some outcomes but often unmeasured in trials, and constructs such as corrective experiences or ongoing reality testing have not been specifically examined in PAP. The authors note methodological challenges inherited from psychotherapy research—most notably the so-called "Dodo Bird Verdict," whereby common factors across therapies reduce detectable differences between approaches in RCTs. They propose that designs such as dismantling studies, comparative efficacy/non-inferiority trials, and cross-lagged panel models could be informative, while acknowledging practical constraints (larger sample sizes, ethical issues, and the relatively small number of sessions in PAP compared with traditional psychotherapy). Finally, the paper flags policy and implementation issues: patchwork legalisation across jurisdictions, the imperative for clear licensure and training standards given participants' heightened vulnerability and suggestibility, and the limited federal funding that has channelled research resources towards drug development rather than psychotherapeutic innovation.

Aday and colleagues interpret the literature as showing early therapeutic promise for PAP but also a marked paucity of empirical work on the psychotherapeutic component. They argue that the field needs to move beyond trial-and-error traditions and community practices by more precisely defining and reporting what psychotherapy entails in PAP, measuring putative mechanisms, and empirically testing which psychotherapeutic components contribute to safety and clinical benefit. The authors position these recommendations within broader psychotherapy research, noting that established practices—such as publishing treatment manuals, specifying provider qualifications, and using designs that can isolate active ingredients—are applicable to PAP. They caution, however, that some standard approaches (for example dismantling designs that remove supportive elements) raise ethical and safety concerns when applied to PAP, and such trials would need to be conducted iteratively with risk mitigation in mind. Cross-lagged panel models and other within-subject longitudinal methods are proposed as complementary strategies to improve causal inference about mechanisms, though the limited number of PAP sessions and the potential for rapid, non-linear change constitute practical hurdles. Key limitations acknowledged include the inconsistent reporting of psychotherapeutic procedures across trials, the scarcity of trials that experimentally manipulate psychotherapeutic variables, and constraints on funding and incentives—industry funding tends to favour drug-focused work because psychotherapy is harder to monetise. Implications discussed by the authors include the need for transdisciplinary research efforts, clearer standards for therapist training and licensure to mitigate risks arising from participant suggestibility, and targeted investment (including public funding) to support rigorous study of the psychotherapeutic elements of PAP so that clinical guidelines and regulatory policies can be evidence-based.

Recent clinical trials of PAP have demonstrated preliminary therapeutic benefits for several health conditions, but there remains considerable ambiguity and limited empirical investigation regarding the psychotherapeutic component of these interventions. Given the sensitivity of psychedelic effects to context and the potential safety and efficacy implications of psychotherapy, the authors conclude that more research is needed to identify best practices, leverage methodological advances from traditional psychotherapy research, and inform regulation and clinical guidelines. They argue that state approvals for PAP and calls from funding bodies to clarify mechanisms of change increase the urgency for investment and innovation in psychotherapy research within the psychedelic field to reduce adverse effects, optimise outcomes, and improve comparability of study findings.