Interest in psychedelic therapies is booming, with hundreds of studies in process. Despite the interest, there are no approved psychedelic treatments for any psychiatric condition. Further, the one large-scale development program using MDMA that reached the FDA was disapproved by the agency for reasons that could apply to clinical trials for classical psychedelics. We review the definitions of...
A persisting debate exists on whether physical processes can fully account for the personal experience of reality or whether subjectivity transcends physical processes. However, scientists and philosophers agree that the subjective experience is influenced by information received from the body and the environment, modulated by emotions, concepts, skills, and memories acquired throughout life....
3,4-Methylenedioxymethamphetamine (MDMA) is used recreationally, as a research tool, and in MDMA-assisted therapy in patients with posttraumatic stress disorder. 3,4-Methylenedioxyamphetamine (MDA) is a psychoactive metabolite of MDMA. Acute effects of MDMA and MDA have never been directly compared in humans. Lysine-conjugated amphetamines slowly release active amphetamine once absorbed,...
Activation of serotonin 2A (5-HT2A) receptors is thought to underly the long-lasting antidepressant effects of psychedelics such as psilocybin, but beyond that, the molecular and cellular mechanisms involved are not well understood. Recent preclinical studies using mice have primarily examined relatively short time points after psychedelic administration, which does not address the long-lasting...
Cannabis products premixed with caffeine are increasingly present in the United States marketplace. Despite emergence of this product class, no human laboratory data have directly evaluated the isolated impact of caffeine on Δ9-tetrahydrocannabinol (Δ9-THC) effects as well as additional impacts of other common co-administered cannabinoids. This double-blind, randomized, placebo-controlled,...
In patients with schizophrenia, cannabis use exacerbates symptoms and can lead to a relapse of psychosis. Some experimental studies in healthy volunteers suggest that pre-treatment with cannabidiol (CBD) may reduce these effects, but others do not. Here, we investigated whether pre-treatment with CBD ameliorates the acute adverse effects of cannabis in patients with schizophrenia. Participants...
Lysergic acid diethylamide (LSD) and 3,4-Methylenedioxymethamphetamine (MDMA) are widely used psychoactive drugs and their potential use in psychiatric medicine is currently generating interest. The mechanism by which these drugs may assist recovery in various disorders such as addiction and post-traumatic stress disorder (PTSD) is still not well understood. Most investigations of the effects...
NeuropsychopharmacologyOctober 2025Aidan L Pham, Ashley E Marquardt, Kristen R Montgomery et al.
Cannabis is the most frequently used illicit drug during pregnancy, with use steadily increasing in the United States as legalization and decriminalization expand to more states. Many pregnant individuals use cannabis to reduce adverse symptoms of pregnancy, considering it to be less harmful than other pharmaceuticals or alcohol. The primary psychoactive component of cannabis,...
NeuropsychopharmacologyOctober 1, 2025Andrew Jin Soo Byun, Harshawardhan U Deshpande, Jessi Stover et al.
Adolescent cannabinoid exposure has been implicated in enduring modifications to adult brain circuitry; however, well-controlled, systematic analyses investigating dose-dependent effects of chronic delta-9-tetrahydrocannabinol (THC) exposure on brain connectivity are lacking. It is hypothesized that large-scale intrinsic networks, such as default mode (DMN), central executive (CEN), and...
Exploring the intricate relationship between brain's structure and function, and how this affects subjective experience is a fundamental pursuit in neuroscience. Psychedelic substances offer a unique insight into the influences of specific neurotransmitter systems on perception, cognition and consciousness. Specifically, their impact on brain function propagates across the structural connectome...
NeuropsychopharmacologyJuly 15, 2025Maria Beatriz Bistue Millón, Laura Noguera, Diana Bruno et al.4 citations
This Phase I clinical trial is the first to rigorously evaluate the safety, tolerability, and pharmacokinetics of a novel sublingual formulation of 5-MeO-DMT, administered at sub-psychedelic doses to adults with moderate to high levels of anxiety and/or depression, without formal psychiatric diagnosis or ongoing treatment. Using a double-blind, placebo-controlled design, participants received a...
3-Methylmethcathinone (3-MMC) is a designer drug that belongs to the group of synthetic cathinones. The compound has been scheduled in many jurisdictions because of public health concerns associated with excessive use. To date, there are no clinical studies that have evaluated the risk profile of 3-MMC in the recreational range of low to moderate doses. The current, first-in-human study (N =...
Working memory relies on synchronised network oscillations involving complex interplay between pyramidal cells and GABAergic interneurons. NMDA receptor (NMDAR) antagonists influence both network oscillations and working memory, but the relationship between these two consequences has not been elucidated. This study aimed to determine the effect of NMDAR antagonists on network oscillations...
This systematic review and network meta-analysis (NMA) sought to compare different antidepressant treatments for treatment-resistant depression (TRD) in order to facilitate evidence-based choices. A literature search of PubMed, Cochrane Library, and Embase from inception until April 13th, 2023 identified randomized, controlled trials (RCTs) of adults with depression who had not responded to at...
Depression affects over 185 million people worldwide, with approximately one-third classified as treatment-resistant depression (TRD). Current treatments, such as oral antidepressants, often take around 3 weeks to become effective, with no immediate anti-suicidal benefits. The field urgently needs innovative therapies that provide rapid relief. Psychedelics like psilocybin and ayahuasca have...
The pharmacologically active (R,S)-ketamine (ketamine) metabolite (2 R,6 R)-hydroxynorketamine (HNK) maintains ketamine's preclinical antidepressant profile without adverse effects. While hypotheses have been proposed to explain how ketamine and its metabolites initiate their antidepressant-relevant effects, it remains unclear how sustained therapeutic actions arise following drug elimination....
The drug development process in psychiatry faces significant challenges due to low reproducibility rates in animal testing, which often leads to translation failures. To address this issue, we introduce a new approach in psychiatric drug development: a preclinical randomized controlled trial (preRCT). To demonstrate its potential utility, we conducted a multi-center preRCT using the alcohol...
Abnormalities during rapid eye movement (REM) sleep contribute to the pathophysiology of major depressive disorder (MDD), but few studies have explored the relationship between REM sleep and treatment-resistant depression (TRD). In MDD, REM sleep abnormalities often manifest as alterations in total night REM Density (RD), RD in the first REM period (RD1), and REM Latency (RL). Among these, RD1...
Acute intoxication from Δ9-tetrahydrocannabinol (THC, the primary active ingredient of cannabis) can lead to neurocognitive impairment and interference with day-to-day operations, such as driving. Present evaluations of THC-induced impairment in legal settings rely on biological drug tests that solely establish cannabis use, rather than cannabis impairment. The current study evaluated the...
While Cannabis use disorder (CUD) is twice as prevalent in males, females transition more quickly from heavy use to CUD and experience more severe withdrawal. These clinically relevant sex differences contrast the lack of knowledge about the underlying brain mechanisms. This study investigated the relationship between CUD and resting-state functional brain connectivity (RSFC), assessing...
Serotonin (5-HT) receptors and N-methyl-D-aspartate receptors (NMDARs) have both been implicated in stress-induced psychiatric disorders. However, there is a paucity of studies evaluating the effectiveness of novel combinatorial pharmacological treatments to treat stress-related disorders. Here, we evaluated whether administration of combinatorial (R,S)-ketamine, an NMDAR antagonist and Food...
Subanesthetic ketamine is currently used as a rapid-acting treatment for varied neuropsychiatric disorders. However, the mechanistic underpinnings of its therapeutic action remain unclear, and emerging clinical and preclinical evidence highlights a potential involvement of the opioid system. We used pharmacological functional ultrasound imaging data acquired during and after ketamine...
Mood dysfunction is highly prevalent in Parkinson's disease (PD), a main predictor of functional decline, and difficult to treat-novel interventions are critically needed. Psilocybin shows early promise for treating depression and anxiety, but its potential in PD is unknown, as safety concerns have excluded people with neurodegenerative disease from previous trials. In this open-label pilot...
Major depressive disorder (MDD) is associated with disruptions in glutamatergic and GABAergic activity in the medial prefrontal cortex (mPFC), leading to altered synaptic formation and function. Low doses of ketamine rapidly rescue these deficits, inducing fast and sustained antidepressant effects. While it is suggested that ketamine produces a rapid glutamatergic enhancement in the mPFC, the...
There is an ongoing need to identify novel pharmacological agents for the effective treatment of depression. One emerging candidate, which has demonstrated rapid-acting antidepressant effects in treatment-resistant groups, is nitrous oxide (N2O)-a gas commonly used for sedation and pain management in clinical settings and with a range of pharmacological effects, including antagonism of NMDA...