Frontiers in Psychiatry
June 12, 2023
Rayyan Zafar, Maxim Siegel, Rebecca Harding et al.
95 citations
Psychedelic therapy is regaining scientific and medical interest, with growing evidence for its safety and efficacy in treating psychiatric disorders, including addiction. This review charts research on these interventions for addiction, starting with the socioeconomic impact of addiction and current treatment options. It examines historical studies from the mid-late 1900s, real-world evidence from naturalistic and survey-based studies, and modern clinical trials from first-in-human to phase II. The review also covers translational neuropsychopharmacology techniques like fMRI and PET that help explain therapeutic mechanisms. A better understanding of these treatment effects can optimize psychedelic therapy development and improve patient outcomes.
Molecular psychiatry
September 1, 2023
Matthew B Wall, Rebecca Harding, Rayyan Zafar et al.
39 citations
Psychedelic therapy shows promise for treating depression, addiction, PTSD, and other psychiatric disorders. Classic serotonergic psychedelics like psilocybin and LSD act primarily at the 5-HT2A receptor, while ketamine, MDMA, and ibogaine also show potential. Modern neuroimaging techniques, especially PET and MRI, now allow precise measurement of brain effects. Key knowledge gaps remain: the link between acute drug effects and long-term clinical outcomes, detailed characterization of 5-HT2A receptor effects, and the role of neuroplasticity. Future studies combining PET with 5-HT2A-selective ligands like [11C]Cimbi-36 and MRI could bridge molecular, functional, and clinical understanding.
Annales Médico-psychologiques revue psychiatrique
September 28, 2021
Vincent Verroust, Rayyan Zafar, Meg J. Spriggs
16 citations
Psilocybin, a hallucinogen, shows promise in treating anorexia nervosa, with a recent study involving 30 participants indicating significant improvements. After therapy sessions incorporating psilocybin, 70% of participants reported reduced eating disorder symptoms, and 60% experienced weight gain within three months. This suggests potential for psychedelics in psychiatry and psychology, offering new avenues for those struggling with eating disorders. With growing interest in complementary and alternative medicine studies, psilocybin's role in psychoanalysis could reshape treatment approaches in mental health.
Drug Science Policy and Law
September 1, 2025
David Nutt, David Erritzøe, Anne Katrin Schlag et al.
9 citations
The field of psychedelic research lacks standardized terminology for clinical development, dosing, safety monitoring, and regulatory classification. A comprehensive framework is proposed that classifies psychedelics by pharmacology (serotonergic, glutamatergic, kappaergic, GABAergic, and atypical), introduces dose-dependent categories (microdose, minidose, mididose, macrodose), and standardizes terms like “short-acting” with specific pharmacokinetic parameters. Safety considerations include cardiovascular and psychological effects, with risk mitigation protocols for higher-risk compounds like ibogaine. A three-phase treatment model—preparation, dosing, and integration—is recommended as a minimum standard. The lack of comparative research on psychotherapy modalities is identified as a critical gap.
Neurotrauma reports
January 1, 2023
Stephanie Karzon Abrams, Brenden Samuel Rabinovitch, Rayyan Zafar et al.
5 citations
People with spinal cord injury (SCI) who use classical serotonergic psychedelics such as psilocybin and LSD often experience intense muscle spasms, sweating, and tremors, a phenomenon not previously described in academic literature. These symptoms resemble a peripherally dominant serotonin syndrome-like clinical picture and can interfere with any beneficial effects. The authors propose a theoretical framework for this hypersensitivity and call for awareness to guide harm reduction, informed consent, and development of protocols that allow safe use of psychedelic-assisted therapy in this population.
June 30, 2022
Matthew B. Wall, Rebecca Harding, Rayyan Zafar et al.
3 citations
preprint
Psychedelic therapy shows potential for treating psychiatric disorders like depression, addiction, and PTSD. Classic serotonergic psychedelics such as psilocybin, LSD, DMT, and 5-MeO-DMT are the main focus, along with ketamine, MDMA, and ibogaine. The concurrent use of advanced neuroimaging methods, particularly PET and MRI, has allowed precise assessment of brain effects, benefiting the development of these treatments. The text identifies gaps in knowledge that future multimodal imaging studies could address, providing a stronger foundation for psychedelic therapy.
Drug Science Policy and Law
January 1, 2022
Rayyan Zafar, Dustin Sulak, Jaime Brambila et al.
3 citations
A 49-year-old woman with metastatic breast cancer (ER+, PR-, HER2+, BRCA-) received targeted chemotherapy and a ketogenic diet for 26 months, then added a high-dose cannabinoid regimen (CBD and THC) and psilocybin-assisted psychotherapy. After five months, PET/CT scans showed no evidence of metastatic disease, and chemotherapy was stopped. A one-year follow-up CT found no residual or recurrent disease. Recurrence appeared at 18 months, when the cannabis dose had been reduced to 60% of the initial protocol; increasing it back to the original dose was followed by receding cancer progression over 16 months. The case suggests potential therapeutic utility of adjunctive cannabinoids and psychedelics in metastatic breast cancer.
Spiral (Imperial College London)
December 30, 2025
Rayyan Zafar
Only 1.8% of people with substance use disorders receive effective treatment, revealing a gap between neuroscience research and clinical care. This paper argues for shifting addiction neuroscience from a diagnostic focus to a theragnostic framework, using biomarkers like fMRI, EEG, and PET to guide treatment decisions and predict outcomes. Psychedelic compounds such as psilocybin, which engage neuroplasticity and reward networks, offer an opportunity to integrate these biomarkers into clinical trials. The authors propose a roadmap for embedding biomarkers in early and late phase trials, drawing on ongoing studies at Imperial College London in gambling and opioid use disorders. Realizing this vision requires collaboration across academia, industry, regulators, and patient groups.
The International Journal of Neuropsychopharmacology
February 1, 2025
Rebecca Harding, Natalie Ertl, Rayyan Zafar
Both escitalopram and psilocybin therapy reduced impulsivity and anhedonia in people with major depressive disorder, but they altered brain connectivity in different ways. Psilocybin increased connectivity between the amygdala and the left anterior insula and putamen, and between the limbic striatal network and the bilateral insula, paracingulate, and temporoparietal junction. Escitalopram decreased connectivity between the amygdala and the right cerebellum and occipital cortex, and between the limbic striatum and the insula. The escitalopram-induced reduction in limbic striatal–insula connectivity correlated with reduced anhedonia. These results suggest the two treatments affect reward-related brain circuitry through distinct mechanisms.