Submitted:
28 August 2025
Posted:
29 August 2025
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Abstract
Background/Objectives: Patients in palliative care often experience multifaceted forms of suffering that extend beyond physical symptoms, including existential distress, loss of meaning, and emotional pain. Ketamine-assisted psychotherapy (KAP) has emerged as a promising intervention for alleviating such complex forms of suffering, yet models specifically tailored to palliative populations remain scarce. This narrative review synthesizes current evidence on ketamine’s neurobiological, psychological, and experiential effects relevant to end-of-life care, and presents a novel, time-limited KAP model designed for use in palliative settings. Methods: Drawing from both biochemical and psychedelic paradigms, the review integrates findings from neuroscience, phenomenology, and clinical practice. In particular, it incorporates a dual-level experiential framework informed by recent models distinguishing ketamine’s differential effects on self-processing networks: the Salience Network (SN), related to embodied self-awareness, and the Default Mode Network (DMN), associated with narrative self-construction. This neurophenomenological perspective underpins the rationale for using two distinct dosing sessions. Results: The article proposes a short-course, time-limited KAP model that integrates preparatory and integrative psychotherapy, two ketamine dosing sessions (one low-dose and one moderate-dose), concurrent psychotherapy, goals of care discussion (GOCD), and optional pharmacological optimization. The model emphasizes psychological safety, meaning-making, and patient-centered care. The sequential dosing strategy leverages ketamine’s unique pharmacology and experiential profile to address both bodily and narrative dimensions of end-of-life distress. Conclusions: This dissociative-psychedelic model offers a compassionate, pragmatic, and theoretically grounded approach to relieving psychological and existential suffering in palliative care. By integrating neurobiological insights with psychotherapeutic processes, it provides a flexible and patient-centered framework for enhancing meaning, emotional resolution, and quality of life at the end of life. Further research is needed to evaluate its clinical feasibility, safety, and therapeutic efficacy.
Keywords:
1. Introduction
2. Materials and Methods
2.1. Mechanisms of Action
2.1.1. -NMDA Antagonism
- Disinhibition Hypothesis: This hypothesis proposes that ketamine blocks NMDA receptors on GABAergic interneurons, reducing inhibitory control over pyramidal neurons. This disinhibition increases glutamate release in the medial prefrontal cortex (mPFC) and elevates the firing rate of pyramidal neurons. Such a “glutamate surge” promotes AMPA receptor activation relative to NMDA activation, enhancing synaptic activity and potentially contributing to antidepressant effects. Supporting this view, AMPA receptor antagonists or mGluR2/mGluR3 agonists can block ketamine’s behavioral effects, indicating the importance of elevated extracellular glutamate levels [18,19,20].
- Direct Inhibition Hypothesis: This hypothesis suggests that ketamine directly antagonizes NMDA receptors on resting pyramidal neurons, blocking tonic NMDA activation by ambient or spontaneously released glutamate. This blockade reduces suppression of protein synthesis and activates downstream synaptogenic cascades. Increased AMPA receptor activation through this mechanism is also thought to contribute to ketamine’s antidepressant effects [21,22].
2.1.2. BDNF and mTOR Signaling
2.1.3. Structural and Functional Changes
2.1.4. Functional Connectivity Changes
2.1.5. Lateral Habenula and Antidepressant Effects
2.1.6. Salience Network and Default Mode Network
2.2. Short-Course Ketamine Protocol
2.2.1. Ketamine and Substance Use Disorders
2.2.2. Ketamine and Mood
2.2.3. Ketamine and Pain
2.3. Ketamine Models of Care
3. Results
3.1. Psychotherapy-Grade Therapeutic Frame
- A clear, time-limited treatment plan.
- Shared understanding of goals and expectations.
- Boundaries for communication and follow-up.
- Proactive exploration of treatment termination.
3.2. Treatment Phases and Timeline
3.2.1. Preparation Phase (2–3 Sessions)
- Psychoeducation about ketamine’s mechanisms, limitations, and potential benefits.
- Exploration and moderation of treatment expectations.
- Establishment of at least three goals of care tailored to the patient’s values and capacity.
- Orientation to potential psychological content or altered states during ketamine sessions.
3.2.2. Ketamine Sessions (2 Sessions)
- Session 1 (low-dose): ~0.3–0.5 mg/kg IV, primarily for acclimatization and to trigger dissociative experiences.
- Session 2 (moderate-dose): ~0.75–1.0 mg/kg IV, oriented toward deeper emotional or existential processing provided by psychedelic experiences.
3.2.3. Integration Phase (2–3 Sessions)
- Process psychological insights or unresolved emotional material.
- Revisit and refine GOCD.
- Translate subjective experiences into actionable, values-based changes.
- Address potential “termination reactions” and create closure.
3.3. Concomitant Psychotherapy
- Enhanced engagement due to ketamine’s rapid cognitive/emotional effects.
- Psychotherapeutic containment of challenging content.
- A continuity pathway for psychological support beyond the ketamine course.
3.4. Goals of Care
- Reconnecting with loved ones.
- Engaging in spiritually or personally meaningful activities.
- Establishing comfort-enhancing routines or rituals.
- Exploring creative expression or legacy documentation.
3.5. Bridging Biomedical and Psychedelic Paradigms
3.6. Clinical and Ethical Considerations
- Time-limited and feasible within palliative care settings.
- Flexible, allowing for individualized psychotherapy and diverse treatment goals.
- Ethically grounded, emphasizing autonomy, emotional safety, and informed consent.
- Integrated, with communication between ketamine providers, psychotherapists, and palliative care teams.
4. Discussion
5. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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| Model | Biochemical | Psychotherapeutic | Psychedelic |
| Name | Ketamine Infusion Therapy | Ketamine-Assisted Psychotherapy | Psychedelic Therapy |
| Objective | Symptom management | Catalyzing psychological change | Facilitating transformative experiences |
| Focus | Medication effects | Psychotherapy | Subjective experience |
| Number of Sessions | 6 to 12 sessions | 3 to 4 sessions | 1 to 2 sessions |
| Procedure | No preparation or integration | Includes preparation and integration | May or may not include preparation and integration |
| Administration Routes | Intravenous | Oral / Sublingual / Intramuscular / Subcutaneous | Intramuscular / Subcutaneous |
| Treatment Setting | Procedure room | Therapy office | Therapy offices & group settings |
| Component | Description |
| Population | Patients receiving palliative care; capable of engaging in brief psychological interventions |
| Dose & Administration | Two intravenous ketamine sessions (0.3–1. mg/kg over ~40 minutes), spaced ~5–10 days apart |
| Psychological Framework | Preparation, experience, and integration; emphasis on meaning-making, emotional exploration, and patient-centered care |
| Setting | Quiet, comfortable, non-medicalized room; minimal clinical cues |
| Sensory Modulation | Use of blindfolds and curated music playlists to enhance immersive and symbolic experience |
| Framing of Experience | Experiences presented as potentially meaningful reflections of inner states, not random or pathological |
| Therapeutic Stance | Emotional validation over interpretation; process emphasized over content |
| Patient Involvement | Collaborative selection of music, language, and therapeutic orientation; flexibility in session goals |
| Integration | Post-session reflection emphasizing emotional insights, symbolic coherence, and existential relevance |
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