OPEN Foundation

Close this search box.

Antisuicidal Response Following Ketamine Infusion Is Associated With Decreased Nighttime Wakefulness in Major Depressive Disorder and Bipolar Disorder

Share This Post


OBJECTIVE: Insomnia and disrupted sleep are associated with increased risk of suicide. The N-methyl-D-aspartate antagonist ketamine has been associated with reduced suicidal thoughts, but the mechanism of action is unknown. This study sought to evaluate differences in nocturnal wakefulness in depressed individuals who did and did not have an antisuicidal response to ketamine.

METHODS: Thirty-four participants with baseline suicidal ideation diagnosed with either DSM-IV major depressive disorder (n = 23) or bipolar depression (n = 11) between 2006 and 2013 completed nighttime electroencephalography (EEG) the night before and the night after a single ketamine infusion (0.5 mg/kg over 40 minutes). Suicidal ideation was assessed at baseline and the morning after ketamine infusion via several measures, including the Hamilton Depression Rating Scale suicide item, the suicide item of the Montgomery-Asberg Depression Rating Scale, and the first 5 items of the Scale for Suicide Ideation. A generalized linear mixed model evaluated differences in nocturnal wakefulness, as verified by EEG, between those who had an antisuicidal response to ketamine and those who did not, controlling for baseline nocturnal wakefulness. Results were also compared to the sleep of healthy controls (n = 22).

RESULTS: After analyses adjusted for baseline sleep, participants with an antisuicidal response to ketamine showed significantly reduced nocturnal wakefulness the night after ketamine infusion compared to those without an antisuicidal response (F₁,₂₂ = 5.04, P = .04). Level of nocturnal wakefulness after antisuicidal response to ketamine did not differ significantly from nocturnal wakefulness in the control sample but did differ at a trend level (F₁,₄₀ = 3.15, P = .08).

CONCLUSIONS: Reductions in wakefulness following ketamine may point to a biological mechanism underlying the effect of ketamine on suicidal ideation.

Vande Voort, J. L., Ballard, E. D., Luckenbaugh, D. A., Bernert, R. A., Richards, E. M., Niciu, M. J., … & Zarate, C. A. (2016). Antisuicidal response following ketamine infusion is associated with decreased nighttime wakefulness in major depressive disorder and bipolar disorder. Journal of clinical psychiatry. 10.4088/JCP.15m10440
Link to full text

OPEN Foundation

Join ICPR 2022 Online!

ICPR features world-leading experts from many academic disciplines, including psychiatry, psychology, neuroscience, anthropology, ethnobotany, and philosophy who come together to give a scientific conference for academics, therapists, researchers, clinicians, policymakers, and members of the public. Get your ICPR 2022 livestream ticket today and use the code OPENLIVE30 at checkout for a €30 discount.

Learn More


Subscribe to our new OPEN-Minded newsletter to stay in the loop, hear about our events, and become a part of a community dedicated to advancing psychedelics.

By clicking subscribe, I confirm to receive emails from the OPEN Foundation and agree with its privacy policy.

16 July - NDE's and Psychedelic Experiences: Commonalities & Insights