ObjectiveThe ideas presented in this paper are based on a presentation at a festschrift event marking the retirement of Professor Gordon Parker from UNSW, Sydney. Drawing on Gordon's depressive subtyping approach and his critiques of a unitary view of major depressive disorder and treatment-resistant depression (TRD), we aim to (i) explore differing models of ketamine for TRD - biomedical...
Treatment-resistant depression (TRD) affects 30-60% of individuals with major depressive disorder and carries substantial morbidity and healthcare costs. Intravenous (IV) ketamine (KET) is a rapid-acting antidepressant, but benefits are often transient, prompting augmentation to sustain efficacy or improve tolerability. We conducted a systematic review and meta-analysis of randomized controlled...
Ketamine is a rapid-acting antidepressant with demonstrated efficacy in major depressive disorder and treatment-resistant depression, yet the mechanisms by which its molecular actions translate into sustained clinical improvement remain incompletely understood. Prevailing models have emphasized N-methyl-D-aspartate receptor antagonism and downstream glutamatergic signaling; however, convergent...
Dissociative neurological symptom disorder (DNSD), termed functional neurological symptom disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision (DSM-5-TR), presents with neurological symptoms not explained by structural disease.The first line treatment of DNSD is psychotherapy, but when the conflict maintaining the symptoms cannot be put into words,...
Suicide is one of the leading causes of death among adolescents in the United States. The 'Acute Course of Ketamine Versus Midazolam for Recurrence of Suicidality in Adolescents' (TASK), a double-blind, randomized, controlled trial, was designed to examine the signal for efficacy of ketamine, compared to midazolam (active control), in reducing 1) repeat suicidal events, 2) implicit cognition,...
Abstract Post‐traumatic stress disorder (PTSD) is a debilitating disorder with limited pharmaceutical treatment options. Ketamine, a noncompetitive N ‐methyl‐ d ‐aspartate (NMDA) receptor antagonist with rapid‐onset effects, has emerged as a potential treatment, particularly for patients who do not respond to first‐line therapies. This systematic review synthesizes the current evidence on the...
Insomnia and anxiety frequently co-occur with treatment-resistant depression (TRD). This study examined short-term changes in depression, anxiety, and insomnia symptoms post-ketamine in TRD and their inter-relationships. Seventy-one patients with TRD were assessed at baseline and 24 h after intravenous ketamine (0.5 mg/kg). Depression, anxiety, and insomnia were measured using the...
Near-death experiences (NDEs) occasionally include claims of veridical perception — accurate information about the physical environment obtained from a reported out-of-body vantage point, ostensibly without ordinary sensory access. The largest attempt to test this directly (the AWARE I/II studies) placed hidden visual targets, visible only from a ceiling-level vantage point, in resuscitation...
Depressive episodes are common but has great impact either in unipolar or bipolar mood disorder. Medical management of severe depression with suicidal attempts are challenging. The rate of Major Depressive Disorder (MDD) who are non-responders are about 30% of those receiving treatment in research settings. Over the past 15 years, ketamine infusions have demonstrated rapid antidepressant and...
Ketamine has gained increasing attention for its therapeutic potential, yet concerns remain regarding its misuse and the associated complications of its use. Ketamine use and ketamine use disorder can induce psychotic symptoms, but the persistence of such symptoms with chronic use and effective treatment of these symptoms is poorly characterized. Although case reports of ketamine use and...