BMJ open
February 10, 2025
Kathryn Fletcher, Nadine Ezard, Krista J Siefried et al.
1 citation
A pilot study will test the safety and feasibility of combining subanaesthetic ketamine with cognitive behavioural therapy for adults with methamphetamine use disorder. Twenty participants seeking to reduce or stop methamphetamine use will receive three subcutaneous ketamine doses (0.75 to 0.9 mg/kg) at weekly intervals and four therapy sessions over four weeks. The study will measure recruitment time, eligibility rates, treatment completion, retention, and acceptability over eight weeks, and explore changes in methamphetamine use, cravings, withdrawal, quality of life, and treatment satisfaction over 24 weeks. No pharmacological treatments currently exist for this condition, and psychotherapy alone is only moderately effective.
Frontiers in Psychiatry
June 24, 2026
Kathryn Fletcher, Nadine Ezard, Krista J. Siefried et al.
People with methamphetamine use disorder who underwent ketamine-assisted psychotherapy described the treatment as a multi-stage process rather than a simple drug effect. Participants reported that ketamine created a temporary state of reduced emotional and cognitive reactivity, which they called 'psychological space,' making them more receptive to psychotherapy. However, behavioral changes—including reduced methamphetamine use—were variable and depended on ongoing therapeutic engagement, personal motivation, and life context. Participants were uncertain whether improvements came from the ketamine, the therapy, or the supportive environment. Acceptability was generally high when treatment occurred in a structured clinical setting.
AJNR. American journal of neuroradiology
April 24, 2026
Joga Chaganti, Krista J Siefried, Veda S Vyakaranam et al.
In individuals with methamphetamine use disorder, psilocybin administration alongside psychotherapy led to measurable reorganization of large-scale brain networks and local neural synchrony. After the intervention, connectivity within and between attentional, default mode, and salience networks shifted significantly, and local synchrony increased in frontal and sensorimotor regions. Greater reductions in methamphetamine use correlated with recovery of frontostriatal and attentional connectivity, while reduced psychological distress was linked to strengthened integration of attentional and prefrontal-striatal circuits. These findings suggest psilocybin may promote network-level plasticity in stimulant addiction and support the potential of resting-state fMRI metrics as biomarkers of such change.
Addiction
December 22, 2025
Jonathan Brett, Toby Lea, Elizabeth Knock et al.
People with methamphetamine use disorder who took part in psilocybin-assisted psychotherapy reported that the treatment was acceptable and often transformative. Before treatment, participants held tempered hopes for positive outcomes. During the psychedelic sessions, many confronted challenging emotional or psychic obstacles by deliberately 'leaning into' them, a process that led to new understandings of themselves, their personal histories, and their relationships. Resolving these obstacles was associated with a reduced importance of methamphetamine in their lives. The therapeutic relationship—characterized by concentrated attention and deep interpersonal intimacy between participant and therapist—was seen as critical to these positive changes.