Classic Psychedelics as a Psychotherapeutic Aid in the Treatment of Stimulant Use Disorder: a Case Report

This is a single-case clinical report of a 22-year-old Indian–Australian male given the pseudonym "John." Informed consent was obtained and the materials were approved by an internal ethics board. Clinical diagnosis used DSM-5 criteria, with formal diagnoses of major depressive disorder, stimulant use disorder, and cannabis use disorder. John commenced individual focused cognitive behavioural therapy (CBT) in December 2015 in a private Australian mental health clinic. He reported no significant physical health problems and was not taking prescription medication during treatment. Clinical and substance-use history were collected through standard clinical assessment, including family and psychosocial background. The report documents John’s lifetime and contemporaneous use of multiple illicit substances (a detailed list is provided in the case record), the timing and doses of several classic psychedelic experiences, and his self-reported subjective effects. As part of follow-up, the thirty-item revised Mystical Experience Questionnaire (MEQ-30) was administered approximately three months after John’s most recent LSD use, with two additional screening items added to record psychedelic types and recent use. A telephone follow-up occurred in September 2019 and was supplemented by an in-clinic urine toxicology screen to confirm stimulant abstinence. No formal statistical analyses were performed; data are presented descriptively as a clinical case narrative.

John’s background included early-onset depressive symptoms from about age 13, a history of bullying and behavioural problems, a family history of mood disorder and suicide, and multiple prior substance exposures. He first used psychedelics at age 17 and stimulants at 16, developing weekly MDMA use and later intranasal methamphetamine use from age 19 to 20. During a period of repeated psychedelic use over roughly 1.5 years prior to seeking therapy, he reported reductions in cravings for stimulants and noted an impactful experience after ingesting about 3.5 grams of psilocybin-containing mushrooms that prompted him to seek psychotherapy. During therapy John reported using classic psychedelics about five times around the start of his treatment and continued weekly-to-monthly MDMA use until September 2016, when he achieved complete abstinence from all stimulants. In the month before stopping MDMA, he reported two occasions of consuming approximately 200 μg LSD and 100 mg DMT, experiences he identified as instrumental to recognising the emptiness of stimulant highs and catalysing behavioural change. John described psychedelic experiences as facilitating non-judgemental self-observation, cognitive flexibility, and motivation for daily integration practices including meditation and creative activities. When administered three months after his most recent LSD use, the MEQ-30 results indicated scores greater than or equal to 60% of the maximum on each subscale (mystical, positive mood, transcendence of space and time, and ineffability), meeting the authors’ threshold for a ‘‘complete mystical experience.’’ At telephone follow-up in September 2019 John reported roughly 2.5 years of stimulant abstinence; an in-clinic urine toxicology screen was negative for stimulants, while toxicology and self-report indicated continued weekly cannabis use. By mid-2017 he had reduced classic psychedelic use to approximately once per year and had enrolled in, but not completed, the Matrix abstinence-based outpatient program for stimulant dependence (six of twenty weeks completed). John also reported some persistent perceptual changes (heightened texture of bright lights) and social adjustment difficulties following frequent, high-dose psychedelic use.

Amoroso and colleagues interpret this case as suggestive that classic psychedelics may serve as psychotherapeutic aids in the treatment of stimulant use disorder with co-occurring depression, noting that the patient attributed meaningful mood improvement, cessation of stimulant use, and sustained integration practices to his psychedelic experiences. The authors situate these observations within preliminary literature linking mystical-type experiences under psychedelics to therapeutic response and acknowledge emerging neurobiological work that seeks to characterise the psychedelic state. Key limitations acknowledged by the authors include the single-case design and limited generalisability, the inability to disentangle effects of psychedelic use from psychotherapy or placebo effects, and retrospective bias introduced by administering the MEQ-30 across multiple past experiences rather than referencing a single recent session. They also note the potential confounding influence of John’s ongoing cannabis use and that recreational, unsupervised use—particularly at high or frequent doses—carries risks such as psychological distress and persistent perceptual disturbances, which may have contributed to his reported social adjustment difficulties. The authors recommend that future research administer measures like the MEQ-30 and dependence severity scales close in time to specific psychedelic sessions, and pursue controlled clinical investigations of classic psychedelic-assisted psychotherapy for stimulant dependence, including in populations with dual diagnoses. Overall, the discussion frames the case as preliminary and hypothesis-generating: the psycho-spiritual and neurophysiological properties of classic psychedelics warrant further controlled study as adjuncts to psychotherapy for stimulant use disorder, but safety, context of use, and methodological rigour must be central to such research.