The British journal of psychiatry : the journal of mental science
May 13, 2025
Shabnam Hossein, Manivel Rengasamy, Aiyedun Uzamere et al.
3 citations
Ketamine infusion most strongly alleviates sadness both immediately and during the first week after treatment, whereas improvements in suicidal thoughts emerge only after three to four weeks. In a secondary analysis of 152 adults with treatment-resistant depression (38.8% with suicidal ideation at baseline), those randomized to a single 40-minute intravenous infusion of ketamine (0.5 mg/kg) showed greater early improvement in sadness-related symptoms compared with saline. Network analyses revealed that ketamine increased connectivity among depressive symptoms, strengthening interrelationships between residual symptoms. The findings suggest that different depressive symptoms respond to ketamine with distinct time courses and possibly different mechanisms.
Brain, behavior, and immunity
April 4, 2025
Manivel Rengasamy, Benjamin Panny, Zakary Hutchinson et al.
3 citations
In adults with treatment-resistant depression, a single ketamine infusion did not produce detectable changes in blood markers of neurotrophic and inflammatory factors compared with a saline placebo, nor were those markers linked to depression improvement over five days. Among 133 participants, only one subgroup—those with a body-mass index below 25—showed an association: rising levels of interleukin-1 receptor antagonist in the first day after ketamine correlated with less reduction in depression symptoms. The results do not support the idea that peripheral neurotrophic or inflammatory factors mediate ketamine's rapid antidepressant effects, though central nervous system activity may still be involved.
Frontiers in Psychiatry
September 2, 2025
Mina Kheirkhah, Nastasia McDonald, Julia Aepfelbacher et al.
1 citation
Adding mindfulness, music, and a light-occluding eye mask during ketamine infusion for depression did not improve antidepressant effects compared to ketamine alone, but it enriched the subjective experience. Participants in the combined sensory intervention group reported deeper engagement, a stronger sense of connection to reality, increased focus, moments of relief from sadness, and feelings of awe and spiritual insight. However, four individuals in that group reported discomfort. The findings suggest that while the sensory interventions make the experience more meaningful for many, they may cause discomfort for a few, and making them optional could avoid this.
Biological psychiatry
April 15, 2025
Mary L Woody, Rebecca Rohac, Iya Cooper et al.
1 citation
A single intravenous dose of ketamine (0.5 mg/kg over 40 minutes) rapidly reduces attentional bias toward sad stimuli in adults with moderate-to-severe depression. A novel dual-probe video task measuring attentional bias showed good test-retest reliability at one week and one month before treatment. In two studies totaling 83 participants, attentional bias decreased from before to 24 hours after ketamine infusion. In the first study, attentional bias correlated with clinician-rated depressive symptoms at each pretreatment assessment. In the second study, reductions in attentional bias correlated with symptom improvement. The findings suggest that reducing attentional bias may be a cognitive mechanism underlying ketamine's rapid antidepressant effects.