Psychedelic medicine (New Rochelle, N.Y.)
June 1, 2024
Ryan Yermus, John Bottos, Nathan Bryson et al.
13 citations
Ketamine-assisted psychotherapy (KAP) produces sustained reductions in anxiety, depression, and PTSD symptoms lasting up to 5 months after the last session. In a retrospective study of adults with treatment-resistant major depressive disorder, generalized anxiety disorder, or PTSD who received KAP across 11 North American clinics, large treatment effects were detected at 3 months (Cohen's d = 0.75-0.86) and sustained at 6 months (d = 0.61-0.73). Case reductions ranged from 39% to 41% at 3 months and 29% to 37% at 6 months. However, high attrition rates (82% at 3 months, 95% at 6 months) may limit validity of the results.
BJPsych open
September 12, 2025
Karim S Ladha, Jiwon Lee, Gabriella F Mattina et al.
A pilot trial tested the feasibility of a four-week course of nitrous oxide compared with midazolam (an active placebo) for treatment-resistant depression. Forty participants were randomly assigned to weekly one-hour inhalations of either 50% nitrous oxide or 50% oxygen plus intravenous midazolam. Recruitment, withdrawal, adherence, and missing data rates met feasibility criteria. Depression severity, measured by the MADRS scale, changed by -20.5% in the nitrous oxide group and -9.0% in the placebo group. Adverse events were mostly mild to moderate and transient. The results support conducting a full-scale trial.
Experimental and clinical psychopharmacology
April 1, 2023
Brett Melanson, Michael Wolter, Zion Leatham et al.
Exposure to a context previously paired with the effects of ketamine reduced immobility in the forced-swimming test in male rats, indicating a conditioned antidepressant-like response. This effect was not observed with bupropion, but was comparable to escitalopram. The response was not due to changes in general activity or conditioned incentive or aversive states, as no group differences appeared in a place-conditioning test. The findings suggest that drug-environment interactions may contribute to ketamine's sustained antidepressant effects in clinical settings.