In Good Energy  /  Clinical Foundation

The Research

Most people come to therapy knowing what it is. Hypnotherapy is a different story. Despite decades of peer-reviewed research and institutional endorsement from Stanford, Harvard, and the NIH, it still occupies an unfair place on the fringe—associated more with stage shows than science.

This page is the evidence base for that third layer—the science behind what becomes possible when the subconscious is part of the conversation. Consider it an open invitation to look closer.

Last updated  /  Spring 2026  ·  New = published or recognized after 2019

If you are new to the evidence base for hypnotherapy, begin here. These are the most significant overarching studies, meta-analyses, and institutional endorsements — chosen to represent the breadth of what hypnosis has been clinically shown to do.

The evidence for hypnotherapy in ADHD is more robust than most people realize. Adults and children with ADHD are equally — and in some research, more — hypnotizable than the general population. The brain regions involved in hypnotic focus and ADHD attention regulation overlap significantly, giving the intervention a strong neurological rationale. Most notably, a randomized controlled follow-up study found hypnotherapy produced better long-term outcomes than CBT for adult ADHD at six-month follow-up.

Self-esteem enhancement is among the most frequently cited applications of clinical hypnosis — rated highly effective by over 70% of practitioners in a 2023 international survey of nearly 700 clinicians. The research spans children, adolescents, adults, and clinical populations, with consistent findings: hypnotherapy improves both self-esteem and the self-efficacy beliefs that underpin confidence, often more rapidly than talk therapy alone.

Hypnotherapy has a long evidence base in smoking cessation, weight management, and addiction treatment. The smoking cessation literature is particularly strong: multiple studies show hypnotherapy outperforms nicotine replacement therapy and produces significant long-term quit rates.

Smoking Cessation

Weight Management

Addiction

The skin and immune system are particularly responsive to hypnosis-based suggestion, reflecting the deep connections between the nervous system and immune function. These studies offer some of the most direct evidence of mind-body causation in medicine.

Allergies & Immune Modulation

Hormonal & Somatic Effects

The trance state and the ketamine state share neurobiology—heightened subconscious access, softened critical filtering, contact with material reasoning alone can't reach. The studies below are the clinical case for pairing ketamine with structured therapeutic work, and for why hypnotherapy is particularly well-matched to the role.

  • Cognitive Behavioral Therapy to Sustain the Antidepressant Effects of Ketamine in Treatment-Resistant Depression: A Randomized Clinical Trial (Wilkinson et al., 2021)New

    Patients with treatment-resistant depression received six IV ketamine infusions over three weeks. Those who achieved clinical response—defined as 50% or greater improvement in depression severity—were then randomized to either CBT or treatment as usual for an additional 14 weeks. The CBT group showed a moderate effect size advantage in sustained remission (Cohen's d = 0.65). The authors identify ketamine's neuroplasticity window—the time-limited period following infusion during which synaptic reorganization occurs—as the biological rationale for why structured psychotherapy is more effective when delivered in sequence with ketamine rather than in isolation. Psychotherapy and Psychosomatics, 2021.

  • Ketamine Assisted Psychotherapy (KAP): Patient Demographics, Clinical Data and Outcomes in Three Large Practices Administering Ketamine with Psychotherapy (Dore et al., 2019)

    The largest real-world outcomes study of ketamine-assisted psychotherapy to date, drawing on data from 235 patients across three clinical practices. Unlike infusion-only models—where ketamine's psychedelic properties are treated as unwanted side effects to be minimized—all three practices in this study intentionally incorporated psychotherapy alongside ketamine administration, using the expanded state as a therapeutic resource rather than a pharmacological inconvenience. Findings showed meaningful reductions in depression, anxiety, and PTSD across the patient sample, with particularly strong results in older patients and those presenting with severe symptom burden. Journal of Psychoactive Drugs, 2019.

  • Ketamine-Hypnosis Package (KHP): A Clinical Case Study for the Treatment of Depression and Addiction (Adler & Scheib, 2020)New

    The first published clinical case study of a structured Ketamine-Hypnosis Package (KHP)—combining ketamine infusion with hypnotherapeutic guidance and integration sessions. The clinical practice observed that patients who are poorly hypnotizable at baseline—including those with obsessive-compulsive presentations—became meaningfully more suggestible when ketamine and hypnotherapy were combined. Case data showed reductions in craving, improvement in treatment-resistant depression, and support for abstinence. The authors identify this as an understudied area with significant clinical potential. Journal of Psychedelic Psychiatry, 2020.

  • The Potential Role of Hypnotic Suggestion in Ketamine-Assisted Psychotherapy for Depression (Phelps, 2025)New

    Clinical case report of a 71-year-old woman with a 20-year history of treatment-resistant depression. An indirect hypnotic suggestion introduced during a ketamine-expanded state prompted significant behavioral activation and contributed meaningfully to treatment response. The author—noting that research has established ketamine increases hypnotizability, but that no studies had yet formally explored the pairing—called hypnotherapy "an excellent modality to pair with ketamine" specifically because it can harness ketamine's heightened suggestibility to facilitate behavior change. The Journal of Clinical Psychiatry, 2025.

  • Psychedelics and Hypnosis: Commonalities and Therapeutic Implications (Lemercier & Terhune, 2018)

    Foundational theoretical and empirical paper establishing the overlapping neurophenomenological features of psychedelic states and hypnosis. The authors propose that the two phenomena share mechanisms—including heightened subconscious access, softened critical filtering, and increased responsiveness to suggestion—and outline a research framework for coupling them at each stage of psychedelic-assisted therapy: preparation, the acute session, and integration. Conclusion: harnessing hypnotic suggestion during and after psychedelic experiences could meaningfully enhance therapeutic efficacy. Journal of Psychopharmacology, 2018.

  • Ketamine as a Possible Moderator of Hypnotizability: A Feasibility Study (Patterson et al., 2018)

    University of Washington School of Medicine pilot study. Low-dose ketamine was administered to participants across hypnotizability ranges. In low-hypnotizable participants, ketamine produced a large-effect-size increase in hypnotic suggestibility scores (Cohen's d = 1.57). The authors concluded this finding warrants further investigation into ketamine's potential to enhance hypnotherapeutic outcomes—and that the dissociative, trance-adjacent state ketamine induces may be mechanistically related to hypnotic responsiveness. International Journal of Clinical and Experimental Hypnosis, 2018.

  • Neuroplasticity as a Convergent Mechanism of Ketamine and Classical Psychedelics (Bhatt et al., 2021)New

    Comprehensive review of preclinical and clinical evidence establishing neuroplasticity as a key downstream mechanism of ketamine's therapeutic effects. Ketamine induces measurable synaptic and structural changes—including synaptogenesis and BDNF-mediated signaling—particularly in prefrontal cortical neurons. The authors describe these neuroplastic shifts as the mechanism through which sustained therapeutic change becomes possible, providing the biological rationale for timed integration work.

  • The Collective Lie in Ketamine Therapy: A Call to Realign Clinical Practice with Neurobiology (Calabrese & Bhatt, 2025)New

    This paper makes a pointed argument directly relevant to how integration is timed and structured: meaningful, lasting improvement requires plasticity-driven reorganization in the days following ketamine administration—not primarily from insights during the acute session. The neuroplastic window begins after ketamine's effects have fully subsided and lasts longer than the window produced by serotonergic psychedelics. Practitioners who overemphasize the acute experience risk distorting the process; those who time integration to the biological window are working with the medicine's actual mechanism. Frontiers in Psychiatry, 2025.

  • Active Mechanisms of Ketamine-Assisted Psychotherapy: A Systematic Review (Joneborg et al., 2022)New

    A 2022 systematic review of five randomized trials of ketamine-assisted psychotherapy found significant positive effects on primary outcome measures versus controls; the authors propose that ketamine's temporary neural changes—NMDA receptor inhibition and increased synaptic neuroplasticity—create a window in which structured therapeutic work produces more durable change than the medicine alone. The review supports a now-foundational argument in the field: integration isn't adjunctive; it's how ketamine's effects become lasting. Journal of Affective Disorders, 2022.

Clinical hypnosis has been used as an adjunct or replacement for general anesthesia, for procedural anxiety and pain reduction, and for accelerating recovery across a wide range of medical and surgical contexts. Cancer care, IBS, and surgery have the largest and most rigorous evidence bases.

Surgery & Wound Healing

Cancer Care

Cancer is one of the most extensively studied areas of clinical hypnosis, with applications from surgical preparation and chemotherapy side effect management through to pain control and palliative care.

Irritable Bowel Syndrome

IBS is one of the best-studied applications of hypnotherapy, now formally endorsed by both European and North American gastroenterology guidelines as a second-line treatment.

Burns, Diabetes, Hypertension & Other Conditions

Research on hypnotherapy for men's health spans sexual function, prostate cancer treatment side effects, and surgical anxiety. The evidence for psychogenic erectile dysfunction is particularly strong, with hypnosis outperforming both testosterone and pharmaceutical interventions in controlled trials.

Sexual Health & Function

  • Hypnosis Better Than Placebo or Testosterone for Male Sexual Dysfunction: An RCT

    79 men with non-organic impotence randomized to testosterone, trazodone, hypnosis, or placebo. Hypnosis achieved an 80% improvement rate, outperforming both testosterone (60%) and trazodone (67%), and was the only treatment statistically superior to placebo. British Journal of Urology, 1996.

  • The Hypnotherapeutic Treatment of Impotence

    Classic clinical study establishing hypnotherapy as an effective treatment for psychogenic erectile dysfunction, addressing both psychological and physiological dimensions through structured suggestion protocols.

  • Hypnosis for Erectile Dysfunction (Araoz, 2005)

    Review of the Ericksonian hypnotic approach to erectile dysfunction, addressing cognitive, emotional, and relational factors. Discusses the role of performance anxiety and negative self-suggestion in psychogenic ED.

  • Hypnotherapy for Psychogenic Impotence: 3,000 Patients with 88% Success Rate (Crasilneck, 1990)

    A Dallas-based clinician reported treating approximately 3,000 patients for psychogenic impotence with an 88% success rate using structured hypnotherapy — one of the largest case series in the literature on male sexual dysfunction and hypnosis.

    Search: "Crasilneck hypnosis psychogenic impotence" to find citation.

Prostate Cancer & Treatment Side Effects

Men undergoing prostate cancer treatment, particularly androgen deprivation therapy (ADT), frequently experience hot flashes, fatigue, mood changes, and anxiety. Hypnotherapy has been studied as a nonhormonal, non-pharmaceutical option for managing these treatment-related side effects.

Hypnotherapy has a robust evidence base across the major mental health categories. Meta-analyses from 2019 onward show consistently large effect sizes for hypnosis in reducing anxiety — larger at long-term follow-up than many standard interventions.

Anxiety

Depression

PTSD

Stress & Exam Anxiety

Aging & Cognitive Health

Hypnotherapy has been studied for neurological conditions including Parkinson's disease, multiple sclerosis, stroke recovery, tinnitus, and bruxism. The common thread is hypnosis' ability to modulate neuromuscular control, pain processing, and psychological adaptation to chronic illness.

Parkinson's Disease

Multiple Sclerosis

Stroke Recovery

Tinnitus

Bruxism, Stuttering & Other Conditions

Pain is the most extensively researched application of clinical hypnosis. Meta-analyses now encompass thousands of participants across chronic pain, procedural pain, surgical pain, and condition-specific pain. The evidence consistently shows medium-to-large analgesic effects, and hypnosis is increasingly recommended as a complement or alternative to opioid-based pain management.

Foundational Meta-Analyses

Headaches & Migraines

Fibromyalgia

Chronic, Neuropathic & Pediatric Pain

Hypnosis enhances focus, imagery vividness, motor learning, and psychological readiness across athletic and academic domains. Research consistently shows benefits for sports performance, flow state entry, academic achievement, and language acquisition.

Sports Performance

Academic Performance & Learning

Hypnotherapy has a strong evidence base for fear-based and behavioral conditions including phobias, trichotillomania, tics, and HPV-related immune responses. For phobias in particular, the speed of resolution under hypnosis is often dramatically faster than standard exposure therapy.

Dental & Medical Fears

Specific Phobias

Tics, Tourette Syndrome & Trichotillomania

Warts & HPV

Wart regression through hypnosis is one of the best-replicated phenomena in psychosomatic medicine, demonstrating direct mind-body modulation of the immune response to HPV.

Hypnotherapy has demonstrated benefits for insomnia, parasomnias, and restorative sleep quality. A notable 2014 study found that hypnosis literally extends the duration of slow-wave deep sleep — with implications for aging, immunity, and cognitive function.

Hypnotherapy has strong evidence across the full arc of women's reproductive health — from fertility through pregnancy, childbirth, and menopause. The menopause section reflects the most significant recent development in the field: in 2023, The Menopause Society awarded clinical hypnosis its highest tier of evidence for hot flash treatment.

Menopause & Hot Flashes New Category

Since 2019, multiple high-quality RCTs and a landmark institutional endorsement have established clinical hypnosis as a first-line option for hot flashes — one of only two nonpharmacological treatments with Level I evidence. Recent comparative research shows hypnosis outperforms CBT on key outcomes.

Fertility

Pregnancy

Childbirth & HypnoBirthing

Research library  /  In Good Energy  /  Amanda K. Reilly, LMHC-D, CCHT

Last updated Spring 2026  ·  New = published or recognized after 2019

All studies linked to PubMed or the publisher's original page where available.

For broken links, search the study title at pubmed.ncbi.nlm.nih.gov or scholar.google.com.