Journal of Psychoactive Drugs
September 23, 2026
Omer A. Syed, Rotem Petranker, Sean M. Nestor et al.
The use of ketamine as a treatment for mood disorders continues to grow in popularity. However, the differences between individuals consuming ketamine within clinical settings and those self-medicating in casual, non-clinical settings has not been yet characterized. Using the 2023 Global Psychedelic Survey, this study aimed to examine the demographic and clinical characteristics, as well as the...
medRxiv
September 11, 2026
Srdjan Sumarac, Tristan Lawson, Leonardo Favi Bocca et al.
preprint
Ketamine and subcallosal cingulate (SCC) deep brain stimulation (DBS) have each shown antidepressant effects in treatment-resistant depression, yet how ketamine modulates SCC physiology during chronic stimulation remains poorly understood. We analyzed 5,907 hours of bilateral SCC sensing, 485 participant-triggered recordings across 193 days, 47 ketamine dosing episodes, and an in-clinic...
The International Journal of Neuropsychopharmacology
September 9, 2026
Omer A. Syed, Fahad Alam, Peter Giacobbe
Abstract Background Major depressive disorder (MDD) is a debilitating medical condition that places a significant psychological, social, and financial burden on the individuals and families of those affected. However, a third of individuals with MDD do not respond to standard treatments – diagnosed with treatment-resistant depression (TRD). Repeated dosing of intravenous (IV) ketamine has...
CNS Drugs
July 1, 2026
Omer A. Syed, Valentyn Sobolenko, Sean M. Nestor et al.
Background and Objective Ketamine and esketamine have emerged as effective and rapid-acting interventions for treatment-resistant depression. Nevertheless, the best-suited candidates for these treatments are not clear. As such, the ability to personalize treatment selection and parameters would likely improve therapeutic response. This systematic review synthesized the literature on clinical...
Neuroscience & Biobehavioral Reviews
January 24, 2026
Omer A. Syed, Benjamin Tsang, Sean M. Nestor et al.
Psilocybin-assisted therapy (PAT) is an emerging intervention for depression. Though several clinical trials report promising results for PAT in treating depression, there remains a need for consensus on optimal methodologies and standardization of PAT protocols. The objective of this review was to assess the efficacy of PAT in treating depressive symptoms and to systematically examine the...
Psychiatry Research
December 29, 2025
Omer A. Syed, Sean M. Nestor, Muhammad Ishrat Husain et al.
1 citation
Psychedelic use has greatly increased within clinical and recreational settings over recent years. While demonstrating a favorable safety profile within certain clinical populations, little empirical research has explored safety of psychedelic use within real-world samples. Using the World Health Organization (WHO) VigiBase, a comprehensive global pharmacovigilance database with voluntary...
Therapeutic advances in drug safety
2025
Gilmar Gutierrez, Gustavo Vazquez, Nisha Ravindran et al.
5 citations
Intranasal (IN) esketamine has become an effective and well-tolerated therapeutic option for the management of treatment-resistant depression within major depressive disorder (MDD-TRD). Despite these promising benefits, given the prevalence of ketamine abuse, concerns remain over the addiction liability that may be associated with esketamine treatment. The objective of this study is to assess...
Psychiatry Research
October 1, 2024
Gilmar Gutierrez, Jennifer Swainson, Nisha Ravindran et al.
17 citations
Intravenous (IV) ketamine and intranasal (IN) esketamine are novel therapies to manage treatment resistant depression within major depressive disorder (MDD-TRD). This is a multi-site observational study aiming to assess the real-world effectiveness and tolerability of these novel therapies in the management of MDD-TRD. 53 patients were referred to receive IV ketamine (n = 26, 69.23 % female,...
Trials
July 3, 2024
Joshua M. Poulin, Gregory E. Bigford, Krista L. Lanctôt et al.
3 citations
Major depressive disorder (MDD) is a leading cause of disability worldwide across domains of health and cognition, affecting overall quality of life. Approximately one third of individuals with depression do not fully respond to treatments (e.g., conventional antidepressants, psychotherapy) and alternative strategies are needed. Recent early phase trials suggest psilocybin may be a safe and...
Research Square
December 28, 2023
Joshua M. Poulin, Gregory E. Bigford, Krista L. Lanctôt et al.
1 citation
preprint
Abstract Background: Major Depressive Disorder (MDD) is a leading cause of disability worldwide across domains of health and cognition, affecting overall quality of life. Approximately one third of individuals with depression do not fully respond to treatments (e.g., conventional antidepressants, psychotherapy) and alternative strategies are needed. Recent early phase trials suggest psilocybin...
BMJ Open
September 1, 2022
Gustavo Vazquez, Gilmar Gutierrez, Joshua D. Rosenblat et al.
6 citations
INTRODUCTION: Esketamine is the S-enantiomer of racemic ketamine and has been approved by the Food and Drug Administration for the management of treatment resistant depression, demonstrating effective and long-lasting benefits. The objective of this observational study is to elucidate the association of intranasal (IN) esketamine with beneficial and negative outcomes in the management of...
Cortex; a journal devoted to the study of the nervous system and behavior
November 2014
Nir Lipsman, Takashi Nakao, Noriaki Kanayama et al.
High activity of the default mode network (DMN) has been proposed to be central in processing self-relevant events. Thus far, this hypothesis of DMN function has not been tested directly using neurophysiological techniques. To test for the link between frontal midline DMN activity and self-relevant processing we measured neuronal activity (single-neurons' firing rates) in human subcallosal...