Journal of Affective Disorders
January 1, 2019
D. Ionescu, Kate H Bentley, M. Eikermann et al.
179 citations
Repeated doses of ketamine did not reduce depression or suicidal ideation more than placebo in outpatients with severe, treatment-resistant depression and chronic suicidal thoughts. Twenty-six medicated adults received six infusions of ketamine or saline over three weeks. Neither depression severity nor suicidal ideation differed between groups during the infusion phase. At three months, two patients in each group had remitted from depression. The authors suggest that the standard 0.5 mg/kg dose may be insufficient for this severely ill outpatient population.
Nature Communications
March 29, 2023
Fangyun Tian, Laura D. Lewis, David W. Zhou et al.
63 citations
Ketamine produces different brain oscillations in distinct regions: gamma oscillations in prefrontal cortex and hippocampus, linked to antidepressant effects, and a 3 Hz oscillation in posteromedial cortex, linked to dissociative effects. By analyzing intracranial recordings from humans and comparing effects with propofol, the authors identified that these frequency-dependent patterns arise from distinct neural circuits, potentially guiding development of biomarkers and treatments for depression.
Anesthesiology
September 4, 2020
Jacob Gitlin, Shubham Chamadia, J. Locascio et al.
48 citations
Ketamine's pain-relieving effects are not solely due to its dissociative properties. In an open-label study, 15 healthy adults received 2 mg/kg of ketamine, with midazolam given later to reduce dissociation. Statistical models showed that dissociation and pain intensity followed similar time courses, but when dissociation scores were added to the pain model, dissociation did not account for the pain relief. This indicates that ketamine's analgesic and dissociative effects are independent, suggesting ketamine can be used to study pain circuits separate from those involved in dissociation.
PAIN Reports
June 3, 2021
Eunice Y. Hahm, Shubham Chamadia, J. Locascio et al.
6 citations
Ketamine given during general anesthesia reduces pain intensity by 3 points and increases dissociation scores by 17.8 points, but these two effects are independent: the pain reduction does not depend on dissociation. This suggests that ketamine's analgesic and dissociative properties involve separate brain circuits, even under general anesthesia, and that ketamine might be developed into a more targeted pain treatment without causing dissociation.