npj Mental Health Research
September 22, 2026
Jack D. C. Dahan, David Dadiomov, Tijmen Bostoen et al.
This response addresses methodological concerns raised regarding our meta-analysis of subjective effects and therapeutic outcomes following ketamine and psilocybin treatment. We discuss the potential influence of psychotherapy and differences in subjective-effect questionnaires across studies, acknowledging these as important limitations. We argue that these factors may partly explain observed...
British Journal of Anaesthesia
February 1, 2025
Simone C Jansen, Monique van Velzen, Elise Sarton et al.
11 citations
The acute hypoxic ventilatory response is a critical chemoreflex originating at the carotid bodies. This study investigates the impact of low-dose i.v. esketamine on the ventilatory response to 20 min of isocapnic hypoxia to test the hypothesis that esketamine does not affect hypoxic ventilation. In this open-label study, 18 healthy subjects received a 3-h escalating i.v. infusion of...
npj Mental Health Research
October 6, 2024
Jack D. C. Dahan, David Dadiomov, Tijmen Bostoen et al.
13 citations
There is some evidence that the subjective effects of ketamine and other psychedelics like psilocybin are crucial for their therapeutic outcomes, such as treatment of depression or substance use disorder (SUD). We performed a meta-analysis and systematic review on the correlation of subjective symptoms and dissociation versus ketamine-induced therapeutic outcomes in patients with depression or...
ACS Pharmacology & Translational Science
July 12, 2024
Albert Dahan, Simone C Jansen, Rutger van der Schrier et al.
8 citations
The anesthetic, analgesic and antidepressant drug ketamine produces dissociation with symptoms of psychosis and anxiety, an effect attributed to neuronal nitric oxide depletion following N-methyl-d-aspartate blockade. There is evidence that dissociation induced by racemic ketamine, containing both ketamine enantiomers (S- and R-ketamine) but not esketamine (the S-isomer) is inhibited by nitric...
Anesthesiology
September 12, 2022
Albert Dahan, Erik Olofsen, Thomas K. Henthorn et al.
3 citations
We thank Bowdle et al.1 for their interest in our article,2 and for the important issue they raise, paraphrased as follows: what is the best anthropocentric description of the "mind-altering" effects of a heterogeneous group of compounds and drugs that act at the brain and cause significant changes in mental state. The group of drugs that we are referring to includes N-methyl-d-aspartate (NMDA)...
Anesthesiology
February 21, 2022
Erik Olofsen, Jasper Kamp, Thomas K. Henthorn et al.
33 citations
BACKGROUND: Ketamine produces potent analgesia combined with psychedelic effects. It has been suggested that these two effects are associated and possibly that analgesia is generated by ketamine-induced dissociation. The authors performed a post hoc analysis of previously published data to quantify the pharmacodynamic properties of ketamine-induced antinociception and psychedelic symptoms. The...
Anesthesiology
July 30, 2017
Kelly Jonkman, Andreas Duma, Erik Olofsen et al.
56 citations
BACKGROUND: Esketamine is traditionally administered via intravenous or intramuscular routes. In this study we developed a pharmacokinetic model of inhalation of nebulized esketamine with special emphasis on pulmonary absorption and bioavailability. METHODS: Three increasing doses of inhaled esketamine (dose escalation from 25 to 100 mg) were applied followed by a single intravenous dose (20...
Brain Connectivity
December 2015
Daniel Kleinloog, Serge A.r.b. Rombouts, Remco Zoethout et al.
This analysis examines the neuronal foundation of drug-induced psychomimetic symptoms by relating the severity of these symptoms to changes in functional connectivity for a range of different psychoactive compounds with varying degrees of psychomimetic effects. The repeated measures design included 323 resting-state functional magnetic resonance imaging time series and measures of subjective...
British Journal of Clinical Pharmacology
February 21, 2013
Marieke Niesters, Christian H. Martini, Albert Dahan
498 citations
The anaesthetic ketamine is used to treat various chronic pain syndromes, especially those that have a neuropathic component. Low dose ketamine produces strong analgesia in neuropathic pain states, presumably by inhibition of the N-methyl-D-aspartate receptor although other mechanisms are possibly involved, including enhancement of descending inhibition and anti-inflammatory effects at central...
Anesthesiology
August 13, 2012
Marieke Niesters, Najmeh Khalili-Mahani, Christian H. Martini et al.
141 citations
Background The influence of psychoactive drugs on the central nervous system has been investigated with positron emission tomography and task-related functional magnetic resonance imaging. However, it is not known how these drugs affect the intrinsic large-scale interactions of the brain (resting-state functional magnetic resonance imaging connectivity). In this study, the effect of low-dose...
Anesthesiology
September 18, 2009
Marnix J. Sigtermans, Albert Dahan, René A. G. Mooren et al.
152 citations
BACKGROUND: Low-dose ketamine behaves as an analgesic in the treatment of acute and chronic pain. To further understand ketamine's therapeutic profile, the authors performed a population pharmacokinetic-pharmacodynamic analysis of the S(+)-ketamine analgesic and nonanalgesic effects in healthy volunteers. METHODS: Ten men and ten women received a 2-h S(+)-ketamine infusion. The infusion was...