The International Journal of Neuropsychopharmacology
September 1, 2026
A Nunes, J E Cunningham, B Leden et al.
Abstract Background Use of intravenous ketamine or intranasal esketamine for depression is frequently limited due to resource requirements and cost. Alternative treatment models have used oral, sublingual or intranasal racemic ketamine, but optimal doses and frequency of administration remain unclear. Dosing modelled from the standard 0.5-1.0mg/kg twice weekly IV ketamine result in transient...
Psychiatry Research
May 12, 2026
Isis Lunsky, Gilmar Gutierrez, Xena Wang et al.
Postpartum Depression (PPD) is a common condition with serious consequences for both mother and baby if left untreated. Currently, few effective strategies exist for prevention of PPD. Ketamine and Esketamine are rapid acting and potent antidepressants, and emerging evidence is showing promising results for PPD. This review searched the MEDLINE, CINAHL, PsycINFO, EMBASE, and Cochrane databases,...
Therapeutic Advances in Psychopharmacology
December 11, 2025
Casimiro Cabrera Abreu, Aleksandar Biorac, Ross J. Baldessarini et al.
Ketamine’s development in psychiatry exemplifies the evolution of psychopharmacology over six decades. Originally introduced as a dissociative anesthetic and psychotomimetic probe, ketamine has been repositioned as a rapidly acting antidepressant, particularly for treatment-resistant depression (TRD). This narrative review draws on historical sources, clinical trials, regulatory documents, and...
Journal of Affective Disorders
October 1, 2025
A. M. Al-Garni, Gustavo Vazquez, Tariq Alotibi et al.
INTRODUCTION Treatment-resistant depression (TRD) represents a significant therapeutic challenge, as conventional treatments demonstrate limited efficacy. Although ketamine's acute antidepressant effects are well-documented, the role of maintenance therapy remains understudied. We conducted a systematic review to assess the efficacy, safety, and optimal implementation strategies of ketamine...
Vertex Revista Argentina de Psiquiatría
July 10, 2025
Micaela Dines, Adriana Bulacia, Paloma Bamondez et al.
Treatment-resistant major depression (TRD) poses a significant challenge in psychiatry due to the limited response to conventional therapies. Subanesthetic dose intravenous (IV) ketamine has emerged as an effective therapeutic option, providing rapid effects on depressive and suicidal symptoms. This article outlines the ketamine infusion protocol implemented in a general hospital, following...
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...
Progress in Neuro-Psychopharmacology and Biological Psychiatry
December 20, 2024
Veronica Grasso, Gilmar Gutierrez, Najat Alzbeidi et al.
9 citations
Unipolar treatment-resistant depression (MDD-TRD) is associated with neurocognitive impairment. Ketamine, an emerging treatment for MDD-TRD, may have neurocognitive benefits, but evidence remains limited. We conducted a systematic search on EMBASE, Google Scholar, PsycINFO, and PubMed and included studies exploring the cognitive effects of intravenous (IV) ketamine treatment in the management...
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,...
Psychiatry Research
May 1, 2024
Gilmar Gutierrez, Melody J Y Kang, Gustavo Vazquez
12 citations
Individuals with major depressive disorder and treatment resistant depression (MDD-TRD) have limited and sometimes poorly tolerated therapeutic options. Low dose ketamine has presented promising and potent antidepressant effects in this population. To support the existent literature, we conducted a longitudinal study examining five years of real-world clinical data on the use of IV low-dose...
Journal of Psychoactive Drugs
November 15, 2023
Anees Bahji, Isis Lunsky, Gilmar Gutierrez et al.
21 citations
There has been a resurgence in psychedelic research for managing psychiatric conditions in recent years. This study aimed to present a comprehensive review of the current state of the field by applying a systematic search strategy for articles on the effectiveness and tolerability of four psychedelic-assisted therapies (psilocybin, lysergic acid diethylamide [LSD],...
EClinicalMedicine
August 1, 2023
Stevan Nikolin, Anthony Rodgers, Andreas Schwaab et al.
166 citations
Background: Intranasal esketamine has received regulatory approvals for the treatment of depression. Recently a large trial of repeated dose racemic ketamine also demonstrated efficacy in severe depression. However, uncertainties remain regarding comparative efficacy, dosage, and the time course of response. Methods: In this systematic review and meta-analysis, we searched Embase, Medline,...
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...
Journal of Affective Disorders
September 1, 2022
Melody J Y Kang, Gustavo Vazquez
BACKGROUND Major Depression is the leading cause of disability worldwide. A cohort of patients do not respond adequately to available antidepressants, leading to treatment-resistant depression (TRD). We evaluated the antidepressant efficacy of an acute intravenous ketamine treatment (0.5 mg/kg) for patients with unipolar TRD, and measured peripheral blood-based biomarkers associated with...
JMIR Research Protocols
May 1, 2022
Gilmar Gutierrez, Joshua D. Rosenblat, Emily R. Hawken et al.
Background Intravenous (IV) ketamine and intranasal (IN) esketamine have been studied as novel alternatives to manage treatment-resistant depression (TRD). The objective of this observational pilot study is to compare the real-world effectiveness and tolerability of IV ketamine and IN esketamine in the management of unipolar TRD. Objective To compare the effectiveness (primary outcome measure)...
Frontiers in Psychiatry
April 25, 2022
M. J. Kang, Emily R. Hawken, Gustavo Vazquez
The mechanism of action underlying ketamine’s rapid antidepressant effects in patients with depression, both suffering from major depressive disorder (MDD) and bipolar disorder (BD), including treatment resistant depression (TRD), remains unclear. Of the many speculated routes that ketamine may act through, restoring deficits in neuroplasticity may be the most parsimonious mechanism in both...
Expert Opinion on Drug Safety
March 9, 2022
Anees Bahji, Carlos A. Zarate, Gustavo Vazquez
71 citations
ABSTRACT Background Racemic ketamine and esketamine have demonstrated rapid antidepressant effects. We aimed to review the efficacy and safety of racemic and esketamine for depression. Research design and methods We conducted a PRISMA-guided review for relevant randomized controlled trials of racemic or esketamine for unipolar or bipolar major depression from database inception through 2021. We...
JMIR Research Protocols
May 11, 2021
A. Philipp-Muller, Taras Reshetukha, Gustavo Vazquez et al.
Background Over one third of patients with posttraumatic stress disorder (PTSD) do not respond to current interventions. Ketamine presents a potential treatment option; however, its effects are temporary. Administering ketamine alongside psychotherapy is one potential means of prolonging its effects; however, only a few studies have investigated this treatment method to date, and none have...
The International Journal of Neuropsychopharmacology
April 30, 2021
Anees Bahji, Carlos A. Zarate, Gustavo Vazquez
62 citations
Abstract Background Ketamine appears to have a therapeutic role in certain mental disorders, most notably unipolar major depressive disorder. However, its efficacy in bipolar depression is less clear. This study aimed to assess the efficacy and tolerability of ketamine for bipolar depression. Methods We conducted a systematic review of experimental studies using ketamine for the treatment of...
Journal of Affective Disorders
September 23, 2020
Anees Bahji, Gustavo Vazquez, Carlos A. Zarate
404 citations
Background: Ketamine appears to have a therapeutic role in certain mental disorders, most notably depression. However, the comparative performance of different formulations of ketamine is less clear. Objectives: This study aimed to assess the comparative efficacy and tolerability of racemic and esketamine for the treatment of unipolar and bipolar major depression. Design: Systematic review and...
BMC Psychiatry
June 2, 2020
J. Phillips, N. Jaworska, Elizabeth Kamler et al.
22 citations
Background Recent evidence underscores the utility of rapid-acting antidepressant interventions, such as ketamine, in alleviating symptoms of major depressive episodes (MDE). However, to date, there have been limited head-to-head comparisons of intravenous (IV) ketamine infusions with other antidepressant treatment strategies in large randomized trials. This study protocol describes an ongoing...
CNS & Neurological Disorders - Drug Targets
2017
Gustavo Vazquez, Sebastian Camino, Leonardo Tondo et al.
Treatments for depression in bipolar disorder (BD) are far less well developed than for unipolar major depressive disorder. Several innovative and experimental approaches have been emerging recently, including use of the dissociative anesthetic ketamine and other antagonists of central NMDA glutamate receptors, as well as unsaturated fatty acids, anti-inflammatory agents, and possibly probiotic...
Journal of Ethnopharmacology
April 1, 1999
Alicia B Pomilio, A A Vitale, Jorge Ciprian-Ollivier et al.
34 citations
The experimental psychosis observed after drinking Ayahoasca, a South American hallucinogenic beverage from the Amazon Indians, reproduces the pathologic transmethylation theory of schizophrenia. This theory postulates a decrease in the monoamine oxidase (MAO) activity, which results in the accumulation of methylated indolealkylamines, such as bufotenin (5-hydroxy-N,N-dimethyltryptamine),...
Aaron Emile Philipp-Muller, Taras Reshetukha, Gustavo Vazquez et al.
BACKGROUND Over one third of patients with posttraumatic stress disorder (PTSD) do not respond to current interventions. Ketamine presents a potential treatment option; however, its effects are temporary. Administering ketamine alongside psychotherapy is one potential means of prolonging its effects; however, only a few studies have investigated this treatment method to date, and none have...