Biological psychiatry
April 1, 2016
Mohamed Sherif, Rajiv Radhakrishnan, Deepak Cyril D'Souza et al.
127 citations
Controlled laboratory studies in healthy humans show that cannabinoid agonists—both plant-derived and synthetic—produce positive, negative, and cognitive symptoms resembling schizophrenia. These effects are time-locked to drug administration, dose-related, and transient. The magnitude of effects is similar to ketamine but qualitatively distinct from other psychotomimetic drugs. In individuals with schizophrenia, cannabinoid agonists transiently worsen symptoms despite antipsychotic treatment, and no beneficial effects have been found, challenging the self-medication hypothesis. Genetic polymorphisms in dopamine-related genes (COMT, DAT1, AKT1) may moderate these effects. Cannabinoid-induced dopamine release does not fully account for the psychotomimetic effects; interactions among endocannabinoid, GABA, and glutamate systems affecting neural oscillations offer a plausible mechanism.
The Psychiatric clinics of North America
June 1, 2023
Shubham Kamal, Manish Kumar Jha, Rajiv Radhakrishnan
32 citations
Interest in using psychedelics to treat treatment-resistant depression is growing, but evidence for classic psychedelics like psilocybin, LSD, and ayahuasca/DMT remains limited, though early results are promising. Atypical psychedelics such as ketamine have also been studied. Researchers caution that the field may be experiencing a hype bubble. Future work should identify the essential components of psychedelic therapies and their neurobiological mechanisms to support clinical adoption.
The Journal of clinical psychiatry
October 2, 2024
Mia C Santucci, Mina Ansari, Sina Nikayin et al.
12 citations
In a real-world clinical setting, 45 patients with treatment-resistant bipolar depression received intravenous ketamine or intranasal esketamine. Among 38 who completed an acute series (twice-weekly treatments for up to four weeks), 39% achieved a clinical response (at least 50% improvement on the Montgomery-Asberg Depression Rating Scale) and 13.2% achieved remission (score of 10 or lower). Mean depression scores dropped from 31.1 to 19.2, a 38.3% improvement. No manic or hypomanic episodes occurred during the acute phase. However, during maintenance treatment, 28.9% of patients experienced hypomanic or manic symptoms, with one severe event requiring hospitalization.
The Journal of Clinical Psychiatry
February 23, 2021
Avinash Hosanagar, Joseph Cusimano, Rajiv Radhakrishnan
1 citation
Psychedelics are being studied as treatments for psychiatric disorders. The FDA has granted Breakthrough Therapy Designations for MDMA-assisted psychotherapy for PTSD and for psilocybin with psychotherapy for treatment-resistant depression and major depressive disorder. Clinical trials are also exploring psychedelics for eating disorders, cognitive impairment, and substance use disorders. This review covers evidence for psilocybin, LSD, MDMA, and ayahuasca. Open-label studies of psilocybin for obsessive-compulsive disorder, depression, and substance use disorders show promising results. Randomized controlled trials of psilocybin for depression and anxiety in advanced cancer found that high-dose psilocybin produced large decreases in depression and anxiety, increased quality of life, and decreased death anxiety, with about 80% of participants sustaining the response at 6-month follow-up.