Journal of psychiatric research
August 1, 2024
Eduardo Igor Torquato Cardoso Lopes, Patrícia Cavalcanti-Ribeiro, Fernanda Palhano-Fontes et al.
9 citations
Subcutaneous esketamine injections given weekly for eight weeks produced a rapid and lasting reduction in suicidality among 18 adults with treatment-resistant depression. Suicidal thoughts dropped within 24 hours after the first dose and remained low throughout the eight-week treatment period. At six months after treatment ended, suicidality was still consistently lower. Clinician ratings showed significant improvement only after two sessions, and 61% of patients achieved remission from suicidal ideation. The findings suggest that weekly subcutaneous esketamine may be a cost-effective way to achieve fast and sustained anti-suicide effects, but controlled studies are needed to confirm these initial observations.
Journal of affective disorders
January 15, 2025
Fernanda Palhano-Fontes, Patrícia Cavalcanti-Ribeiro, Kaike Thiê da Costa Gonçalves et al.
7 citations
Eight weekly subcutaneous injections of esketamine produced a 52.17% response rate and a 34.78% remission rate in 30 patients with treatment-resistant depression, with improvements in self-reported depressive symptoms sustained for up to six months. The open-label trial lacked a control group and had a small sample size, limiting causal interpretation and generalizability. Subcutaneous administration offers a cheaper, easier alternative to intravenous or intranasal routes with comparable plasma levels and fewer side effects.
European archives of psychiatry and clinical neuroscience
October 28, 2024
Kaike Thiê da Costa Gonçalves, Vagner Deuel O de Tavares, Maria Luiza de Morais Barros et al.
5 citations
A systematic review of 29 studies examined whether the psychoactive effects of ketamine are linked to its therapeutic benefits for psychiatric disorders. About half of the studies (51.72%) found a positive relationship between ketamine-induced altered states of consciousness and clinical outcomes, while 44.83% found no link, and one study found a negative association. For mood disorders like major depressive disorder and bipolar disorder, 48% of studies showed a positive relationship and 48% showed none. All three studies on substance use disorder reported a positive correlation. The authors conclude the relationship remains uncertain due to high variability across studies.
European Archives of Psychiatry and Clinical Neuroscience
March 28, 2026
Yves Martins Varela, Vagner Deuel De O. Tavares, Luiza Macedo Delgado et al.
1 citation
Cognitive-behavioral therapies are being combined with psychedelic substances such as ketamine, psilocybin, and MDMA to treat mental disorders, but the way they are integrated varies widely across studies. A systematic review of 9 clinical trials involving 283 patients found that traditional cognitive behavioral therapy was the most common approach, used in 6 studies, while mindfulness-based cognitive therapy and acceptance and commitment therapy were each used in 2 and 1 studies respectively. The timing of therapy relative to the psychedelic experience—before, during, or after—also differed. The findings highlight the need for more consistent research to clarify how these therapeutic models are best implemented.
Journal of clinical psychopharmacology
Vagner Deuel de O Tavares, Kaike Thiê da Costa Gonçalves, Maria Luiza de Morais Barros et al.
1 citation
A meta-analysis of eleven studies found no significant correlation between the psychoactive (psychomimetic) effects of ketamine and clinical outcomes in mental illness, including depression. The overall correlation was r = 0.06, and for depression specifically r = 0.03, both non-significant. Sub-analyses accounting for patient disorders, intravenous administration, assessment instruments, and timing also yielded no significant findings. High heterogeneity was present. The analysis suggests that altered states of consciousness during ketamine sessions are not directly linked to clinical outcomes, but the limited number of studies and heterogeneity make this conclusion preliminary.
medRxiv Preprint Server
May 31, 2026
Yves Martins Varela, Patrícia Cavalcanti-Ribeiro, Geovan Menezes de Sousa et al.
preprint
Ketamine rapidly reduces depression symptoms in treatment-resistant depression, but its effects may be enhanced by combining it with psychotherapy. The drug induces neuroplasticity and psychological openness, which could help patients process emotions, restructure thoughts, and maintain improvements. However, research has not yet thoroughly examined whether adding structured psychotherapy to ketamine treatment provides additional benefits.
Journal of affective disorders
March 15, 2026
Patrícia Cavalcanti-Ribeiro, Lara Carvalho Araújo Melo De Souza, Vagner Deuel O de Tavares et al.
In a small open-label trial of 22 patients with treatment-resistant depression who received seven weekly subcutaneous doses of esketamine, those with elevated baseline C-reactive protein (CRP > 1 mg/L) showed significant reductions in CRP by week 4 and week 8, while patients without inflammation showed no change. By week 8, CRP levels in both groups were comparable. Although the inflammation group had a greater average reduction in depression severity (15.88 points on the MADRS scale versus 11.14 points), this difference was not statistically significant, and changes in CRP did not predict symptom improvement. Larger controlled studies are needed.