International journal of psychiatry in clinical practice
June 1, 2026
Damian Swieczkowski, Aleksander Kwaśny, Michal Pruc et al.
Women made up 62.9% of participants across 13 esketamine clinical trials for mental health disorders, while men comprised 37.1%. The racial distribution showed White participants at 69.08%, Asian at 13.31%, Black or African American at 3.60%, American Indian or Alaska Native at 0.08%, and Native Hawaiian or Other Pacific Islander at 0.04%. Hispanic or Latino representation ranged from 10.57% to 11.02% due to reporting discrepancies in one trial. These trials demonstrate significant racial and ethnic disparities, with underrepresentation of minority groups, highlighting the need for regulatory efforts to improve diversity and fair representation in future research.
Research Square
February 17, 2026
Zofia Winczewska, Magdalena Górska‐ponikowska, Wiesław Jerzy Cubała
Ketamine at 25 ng/mL increased the viability of mouse hippocampal HT22 neuronal cells exposed to hydrogen peroxide, but only at the highest concentration tested (1000 µM H₂O₂). At that level, cell viability rose from 12% (±1.63%) without ketamine to 38% (±9.12%) with ketamine. This suggests a protective, nonlinear effect that depends on the intensity of oxidative stress, activating only at critical H₂O₂ overload typical of severe depression. The findings indicate a threshold antioxidant mechanism that may contribute to ketamine's antidepressant action and inform future predictive models for individualized treatment.
Therapeutic advances in psychopharmacology
January 1, 2026
Zofia Kachlik, Wiesław Jerzy Cubała, Michał Walaszek et al.
Anhedonia, a core symptom of bipolar depression, often fails to improve with ketamine treatment in patients with treatment-resistant bipolar depression. In a retrospective analysis of 31 patients who received eight doses of ketamine, 45.2% did not achieve a 50% or greater reduction in anhedonia scores. Nonresponders tended to have higher body mass index, later illness onset, fewer hypomanic episodes, and lower employment rates. These metabolic, illness-course, and psychosocial factors may help predict which patients are less likely to benefit from ketamine's anti-anhedonic effects.
Therapeutic advances in psychopharmacology
January 1, 2026
Zofia Kachlik, Wiesław Jerzy Cubała, Michał Walaszek
Ketamine and esketamine offer rapid antidepressant and anti-suicidal effects for treatment-resistant depression and bipolar depression, but differ from conventional antidepressants in their acute subjective effects, physiological profile, delivery models, and misuse potential. This narrative review synthesizes evidence from regulatory guidance, clinical trials, observational studies, and qualitative research to identify key patient information needs and proposes practical psychoeducational strategies. Core elements include explanations of indications, mechanisms, and treatment algorithms; guidance on visit preparation, scheduling, and monitoring; management of acute adverse effects; counselling on suicidality and substance misuse; and tailored considerations for special populations such as older adults, women of reproductive potential, and medically complex patients. The review proposes a patient-centred framework for psychoeducation and identifies priorities for future research.
Frontiers in Psychiatry
December 4, 2025
Adam Włodarczyk, Jakub Słupski, Joanna Szarmach et al.
Ketamine may be a viable treatment option for patients with treatment-resistant post-stroke depression. Further research is needed to better understand its efficacy and safety in this specific patient population.
Therapeutic advances in psychopharmacology
January 1, 2025
Aleksander Kwaśny, Wiesław Jerzy Cubała, Alina Wilkowska
Intravenous ketamine is effective for treatment-resistant bipolar depression, with dosing typically based on actual body weight. In a retrospective analysis of 22 inpatients, doses recalculated using formulas for lean body mass, ideal body weight, and body surface area were compared between responders and nonresponders. Body surface area-normalized doses ranged from 17.63 to 23.09 mg/m² in nonresponders and 15.73 to 23.89 mg/m² in responders. Lean body mass and ideal body weight recalculations at 0.5 mg/kg yielded lower relative doses, especially among nonresponders, suggesting potential underdosing. These preliminary findings do not support alternative dosing formulas over actual body weight, but replication in larger controlled studies is warranted.
Magnesium research
Jakub Słupski, Adam Włodarczyk, Natalia Górska et al.
Impulsive behaviors are common in major depressive disorder and bipolar disorder, raising suicide risk and mood instability. Ketamine, an NMDA receptor antagonist, can produce rapid antidepressant and antisuicidal effects, and magnesium given with low-dose NMDA antagonists reduces anxiety- and depression-like behaviors in animals. This observational study of 49 inpatients with treatment-resistant mood disorders measured impulsivity with the Barratt Impulsiveness Scale (BIS-11) and magnesium levels before and during a four-week course of eight ketamine infusions. Magnesium ion concentration during treatment was not associated with changes in BIS-11 scores. The findings provide no evidence for a relationship between magnesium levels and impulsivity during ketamine therapy.