Trends in Psychiatry and Psychotherapy
May 27, 2025
Mariana V. F. Echegaray, Rodrigo P. Mello, Guilherme M. Magnavita et al.
11 citations
Among people with treatment-resistant depression, the intensity of dissociation caused by a single infusion of ketamine or esketamine is linked to greater antidepressant effect one day later, but only when dissociative symptoms are mild to moderate. For every one-point increase on a dissociation scale up to 15 points, depression scores improved by an average of 0.5 points after 24 hours. This relationship was not observed at 72 hours or 7 days after infusion. The study was not originally designed to test this relationship, so confounding factors were not controlled, and the finding should be considered suggestive rather than definitive.
European archives of psychiatry and clinical neuroscience
December 16, 2024
Gustavo C Leal, Isabel Lima-Araújo, David G Roiter et al.
7 citations
Arketamine, an enantiomer of ketamine, has been less studied than esketamine or racemic ketamine, but recent preclinical work suggests it may have prolonged antidepressant effects and a better safety profile. This scoping review of 20 studies involving 410 subjects found arketamine was primarily investigated for pain management and depression. Early evidence indicates it may reduce pain, though most studies were small and in non-clinical settings. In psychiatry, trials show potential antidepressant effects, but results are inconsistent and some studies unpublished. A consistent finding is arketamine's favorable safety profile, with fewer dissociative and psychotomimetic effects than esketamine or racemic ketamine. Larger, well-designed studies are needed to determine its therapeutic potential.
Psychiatry research
July 1, 2024
Ana Paula Anzolin, Daniel Prates Baldez, Bruno Braga Montezano et al.
2 citations
Subcutaneous ketamine substantially reduced suicidal thoughts and depressive symptoms in patients with severe depression. In a naturalistic study at a Brazilian hospital, 26 patients with a current depressive episode received adjustable ketamine doses starting at 0.5 mg/kg. After about eight sessions, most patients achieved remission of suicidal ideation, as measured by the Columbia Suicide Severity Rating Scale. Higher ketamine doses were associated with greater improvements in depression, suicidal ideation, and overall functioning. Improvements were sustained over six months of follow-up in 18 patients. Side effects were minor and short-lived. The findings suggest subcutaneous ketamine is a promising, well-tolerated, and potentially cost-effective treatment for severe depression with suicidal tendencies, warranting further controlled trials.
Journal of psychiatric research
August 1, 2023
Igor D Bandeira, Gustavo C Leal, Fernanda S Correia-Melo et al.
In a pilot trial of six people with bipolar I or II disorder who had been depressed for at least four weeks, two intravenous infusions of arketamine (0.5 mg/kg followed one week later by 1 mg/kg) rapidly reduced depression severity. Depression scores on the Montgomery-Åsberg Depression Rating Scale fell from a baseline mean of 36.66 to 27.83 one day after the first infusion and from 32.0 to 17.66 one day after the second infusion. The drug was well tolerated with almost no dissociation and no manic symptoms. The findings suggest arketamine has rapid-acting antidepressant properties for bipolar depression, consistent with earlier animal research on major depression.