Interleukin-6 (IL-6) has been implicated as a potential predictor of ketamine response in treatment-resistant depression (TRD). Esketamine, the S-enantiomer of ketamine, produces rapid antidepressant effects and offers improved safety and intranasal administration. To examine whether baseline IL-6 predicts treatment response to esketamine in individuals with TRD. Fourteen adults with TRD...
Previous systematic reviews and meta-analyses have reported impressive antidepressant effects of ketamine in treatment-resistant depression (TRD). While ketamine has been compared with electroconvulsive therapy (ECT), the gold standard treatment, the extent and durability of its antidepressant effects over longer periods remain unclear. To our knowledge, this is the first systematic review...
3,4-methylenedioxymethamphetamine (MDMA) is being investigated as a new therapy for post-traumatic stress disorder (PTSD). With antidepressants as the first-line pharmacotherapy for PTSD, it is important to understand any drug-drug interactions between antidepressants and MDMA. This study aimed to investigate the association between antidepressant use and MDMA fatality using a drug-death...
The trajectory and predictors of response under routine clinical care of esketamine nasal spray (ESK NS) over treatment-resistant depression (TRD) require elucidation. This retrospective, longitudinal cohort study was conducted across three Spanish centers. Adults diagnosed with TRD who initiated ESK NS and completed at least the induction phase were included. Assessments occurred at baseline,...
Ayahuasca has aroused increasing interest due to its therapeutic effects. However, its effects on cognition are poorly understood. Hence, a systematic review evaluating the cognitive effects of ayahuasca was conducted. This systematic review was conducted in accordance to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. A comprehensive search was performed in...
Cannabis constituents, including Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), show distinct pharmacological profiles with therapeutic relevance for neurological and psychiatric conditions. THC exerts euphoric effects primarily via CB1 receptor activation, while CBD displays non-euphoric properties affecting various pathways. This study evaluated the effects of THC, CBD, and their...
One of the most robust acute effects of cannabis is impaired memory. Although memory is not a unitary construct, most cannabis research has focused on verbal memory. Less is known about its effects on more ecologically valid domains of memory, such as prospective and temporal order memory. We conducted a randomized, double-blind, placebo-controlled study to map out which aspects of memory are...
Classical psychedelics-a broad class of compounds that include psilocybin, lysergic acid diethylamide, dimethyltryptamine, and mescaline-have shown significant promise for the treatment of mental health conditions in recent clinical trials. Organizations such as the National Network of Depression Centers (NNDCs) can play a pivotal role in uniting researchers and clinicians working in this field...
To investigate the reporting of harms in systematic reviews (SRs) focused on hallucinogen use. A search was conducted in May 2022 using MEDLINE, Embase, Epistemonikos, and Cochrane databases to retrieve SRs focused on the use of hallucinogens. Investigators screened the titles and abstracts from the search for study inclusion in a masked, triplicate fashion. Investigators analyzed the included...
Indigenous Peoples have cultivated and protected natural psychoactive medicines through ceremony, kinship, and spiritual responsibility across generations, yet their long-standing contributions have often been marginalized through extractive research, commercialization, and policy exclusion. It is Indigenous communities that have stewarded and gained expertise working with psychoactive...
Lysergic acid diethylamide (LSD) has been considered as a potential treatment for depression for over 75 years, but its therapeutic potential has only recently been considered in mainstream psychiatry. Repeated ingestion of low doses of LSD ("microdoses") is thought to reduce depression, but the neurobiology underlying this effect is unknown. We previously reported that low doses of LSD...
Abuse potential assessment of drugs with central nervous system activity is a critical component of the development of new medications for regulatory filings for approval worldwide. These new drug applications typically include recommendations for scheduling status as a controlled substance, if scheduling is warranted. This commentary focuses on the approach and current issues related to...
This review provides an overview of Roland R. Griffiths' history of research, and his mentoring and collaborating approach to science that contributed to his impact in behavioral and neuropsychopharmacology and psychedelic medicines development. The approach was to summarize studies in his major domains of research, including preclinical and clinical abuse liability assessment science, alcohol,...
The Altered States of Consciousness Scale (3/5D-ASC or 11-ASC) is widely used to assess non-ordinary states of consciousness, particularly for psychedelic research. However, its original dimensional model (3D-ASC within 5D-ASC) and later 11-subscale structure (11-ASC) have a hierarchically incompatible higher/lower-order structure. Although the 11-ASC offers superior model fit, the 3D-ASC...
Ketamine, known for its rapid-acting antidepressant effects, is often coadministered with other psychoactive drugs, including opioids and cannabinoids, in both clinical and recreational settings. We investigated whether ketamine (R-, S-, or racemic R, S-) isoforms alter the subjective effects of morphine or Δ9-tetrahydrocannabinol (THC) and whether the interoceptive effects of ketamine overlap...
"Psychedelic research - Going global" is a Special Issue of the Journal of Psychopharmacology that has been compiled and published as a tribute to Dr. Roland R Griffiths in recognition of his pioneering and pivotal contribution to the field of psychedelic research. Dr. Griffiths was Professor in the Departments of Psychiatry and Neurosciences at Johns Hopkins University School of Medicine, and...
Little is known about whether 3,4-methylenedioxy-N-methamphetamine (MDMA) neurocognitive side effects improve with sustained abstinence. This study aimed to systematically review and synthesise the existing literature on the long-term neurocognitive side effects of recreational MDMA use after a minimum of 6 months of abstinence. We searched relevant databases utilising terms related to (1) MDMA...
While psychedelics are often claimed to enhance creativity, their precise effects on distinct stages of creative cognition remain poorly understood. This study investigated the acute effects of an ayahuasca-inspired formulation combining N,N-dimethyltryptamine (DMT) and harmine (DMT/HAR), as well as harmine alone (HAR), on micro-level (divergent/convergent thinking) and macro-level (creative...
Subanesthetic doses of ketamine produce complex neuropsychiatric effects, which include rapid psychotomimetic symptoms and antidepressant effects that can last several weeks. Despite over 60 years of research, the mechanism(s) of action underlying ketamine's effects in the brain remains largely mysterious. Neurophysiological field potential recordings provide a direct window into brain...
Diarylethylamine drugs possess dissociative properties. These emerged as drugs of misuse, with reports of strong addictive potential, high tolerance and compulsive intake. Since one of these drugs, diphenidine, was added to the 1971 Convention on Psychotropic Substances, the United Kingdom (UK) had to consider its control. The Advisory Council on the Misuse of Drugs 2023 advice included...
Hexahydrocannabinol (HHC) recently appeared on the recreational drug market and is often sold as a legal replacement for Δ9-tetrahydrocannabinol (Δ9-THC). Users primarily consume HHC for recreational purposes, but adverse effects have been reported. Given the scant literature on HHC, additional research is needed to better understand its effects. The present study sought to determine whether...
Ketamine has emerged as a putative rapid-acting treatment option for psychiatric disorders, particularly treatment-resistant depression. Chronic recreational ketamine use is associated with ketamine-induced urological toxicity, raising concerns over the safety of repeated ketamine treatments. This systematic review aimed to synthesise urological findings from clinical trials and observational...
This study aimed to validate and culturally adapt the Altered States of Consciousness Rating Scale (OAV) and Five Dimensional-Altered States of Consciousness Questionnaire (5D-ASC) for Brazilian Portuguese to measure altered states of consciousness in the context of psychedelic research. A parallel back-translation model was employed with expert reviews to ensure linguistic and cultural...
Ketamine, a rapid-acting N-methyl-D-aspartate receptor antagonist used as a therapeutic for treatment-resistant depression (TRD), is usually administered intravenously or intranasally. This randomized, double-blind, placebo-controlled, Phase 1 study investigated safety and tolerability (primary endpoint), pharmacokinetics (PK) and pharmacodynamics (PD) of an immediate-release oral ketamine....
Mindfulness and compassion are therapeutically relevant and can be increased through different forms of meditation practices. However, meditation practice needs time and commitment. These resources are often limited in patients with mood disorders. Therefore, efficacious remedies that increase mindfulness and compassion could provide therapeutic options. This study aimed to investigate the...