Research Square
July 9, 2026
Samuel Westenhöfer, Yamina Ehrt, Barbora Provaznikova et al.
Abstract Background : Treatment-resistant depression (TRD) is associated with substantial clinical and socioeconomic burden. Intranasal esketamine has shown efficacy for TRD in clinical trials and real-world studies. However, evidence on optimal maintenance scheduling is limited. We therefore investigated whether two maintenance schedules differing in their inter-dose intervals were associated...
Psychotherapy and Psychosomatics
June 19, 2026
Judith Rohde, Tyler M Moore, Kathryn Walker et al.
Ketamine combined with psychotherapy has shown promise in treating posttraumatic stress disorder (PTSD), but predictors of clinical benefit remain unclear. In this systematic review and individual participant data meta-analysis (IPDMA), we examined patient- and treatment-level predictors of PTSD symptom change after combined treatment. Eligible studies combined ketamine with psychotherapy in...
Progress in Neuro-psychopharmacology and Biological Psychiatry
2026
Cheng-Teng Ip, Sebastian Olbrich, Mateo de Bardeci et al.
1 citation
BACKGROUND: Recent advancements in psychedelic research have highlighted psilocybin's potential therapeutic benefits for various mental disorders. Understanding its effects on brain function and identifying predictors of individual responses are essential for developing effective treatments. METHODS: This double-blind, randomized, crossover, and placebo-controlled study enrolled 25 healthy...
Therapeutic Advances in Psychopharmacology
2026
Yujuan Liu, Xiaorong Liu, Sebastian Olbrich et al.
Ketamine has emerged as a promising rapid-acting antidepressant for treatment-resistant depression (TRD), yet its mechanisms of action and reliable biomarkers of treatment response remain poorly understood. Recent evidence suggests that the aperiodic exponent (1/f slope) of electroencephalography (EEG) power spectra reflects cortical excitation-inhibition balance (EIB), offering a potential...
December 10, 2025
Johannes Jungwirth, Samuel Westenhöfer, Helena Aicher et al.
Abstract Psilocybin has demonstrated promising antidepressant effects in depression and treatment-resistant depression (TRD) in controlled clinical trials. However, its effectiveness and safety in real-world therapeutic settings remain largely unknown. Although psilocybin is not yet approved as an antidepressant treatment, Switzerland’s unique legal framework allows its limited medical use for...
Journal of Affective Disorders
November 22, 2025
Carlos Trenado, Erich Seifritz, Sebastian Olbrich et al.
4 citations
Ketamine and its enantiomer esketamine are NMDA receptor antagonists that have shown consistent antidepressant effects in major depression disorder (MDD). These effects suggest an active role of glutamate in the pathophysiology of depression. It has been hypothesized that acute increase of glutamate neurotransmission in the prefrontal cortex following treatment with (es)ketamine leads to...
Journal of Affective Disorders
October 1, 2025
Weng-Lam Chan, Sebastian Olbrich, Xinwen Jiang et al.
3 citations
Major depressive disorder, particularly its treatment-resistant form (TRD), poses significant treatment challenges. Ketamine, an N-methyl-d-aspartate receptor antagonist, has shown promise in rapidly alleviating depressive symptoms by influencing neuroplasticity and glutamatergic modulation, which are thought to influence brain activity complexity. In this placebo-controlled study, we examined...
European Archives of Psychiatry and Clinical Neuroscience
September 1, 2025
Golo Kronenberg, Georgios Schoretsanitis, Erich Seifritz et al.
Nitrous oxide (N2O) has been known since the end of the eighteenth century. Today, N2O plays a huge role as a greenhouse gas and an ozone-depleting stratospheric molecule. The main sources of anthropogenic N2O emissions are agriculture, fuel combustion, wastewater treatment, and various industrial processes. By contrast, the contribution of medical N2O to the greenhouse effect appears to be...
BMJ Open
July 16, 2025
Golo Kronenberg, Anna Bankwitz, Barbora Provaznikova et al.
Suicidal thoughts and behaviours are linked to a wide range of mental health conditions. New interest in the psychiatric benefits of nitrous oxide (N2O) has only recently emerged. The broad pharmacological effects of N2O are thought to be due in large part to N-methyl-d-aspartate antagonism and opioid effects. The purpose of this study protocol is to test whether inhalational N2O exerts rapid...
Psychiatry research. Neuroimaging
July 1, 2025
Anna Monn, Corinne Eicher, Annia Rüesch et al.
2 citations
Treatment-resistant depression (TRD) is associated with reduced quality of life and elevated mortality, posing a major challenge to psychiatric care. After non-response to conventional treatments, next-level interventions such as (es)ketamine are recommended, though remission rates remain variable. Identifying reliable markers of treatment response is therefore critical. Recent evidence...
Therapeutische Umschau. Revue therapeutique
April 1, 2025
Tobias Bracht, Daniela Hubl, Kristina Adorjan et al.
1 citation
Depression is one of the most common mental disorders. The effectiveness of pharmacological and psychotherapeutic treatments is well documented. Remission rates are around 67 % for pharmacological antidepressant initial and secondary treatment of a depressive episode in unipolar disorders. However, patients with a depressive episode who do not respond to at least two successive attempts at...
Behavioral sciences (Basel, Switzerland)
August 16, 2024
Judith Rohde, Elena Hickmann, Marco Buchmann et al.
7 citations
This pilot case series investigated the feasibility and efficacy of an eight-week therapy program, combining nasally administered ketamine (0.5 mg/kg) with trauma-focused psychotherapy, for individuals with chronic, treatment-resistant post-traumatic stress disorder (PTSD). Three patients with chronic, treatment-resistant PTSD underwent the eight-week therapy program. Clinical assessments...
Psychophysiology
March 27, 2021
Sebastian Olbrich, Katrin H. Preller, Franz X. Vollenweider
34 citations
Abstract The interest in lysergic acid diethylamide (LSD) has sparked again due to its supposed positive effects on psychopathological conditions. Yet, most research focuses on the actions of LSD on the central nervous system. The interaction with the autonomic nervous system (ANS) has been neglected so far. Therefore, the aim was to assess the effects of LSD and the serotonin 2A receptor...
Clinical Neurophysiology
March 14, 2021
Torsten M. Meyer, Martin Brunovský, Jiřı́ Horáček et al.
25 citations
OBJECTIVE: Ketamine has been shown to be effective in treatment of episodes of major depressive disorder (MDD). This controlled study aimed to analyse the predictive and discriminative power of heart rate (HR) and heart rate variability (HRV) for ketamine treatment in MDD. METHODS: In 51 patients, HR and HRV were assessed at baseline before and during ketamine infusion and 24 hours post...