Lancet psychiatry
November 1, 2022
S. Smith-Apeldoorn, J. Veraart, J. Spijker et al.
163 citations
Ketamine can quickly reduce depression in people who do not respond to other treatments, but the effect often fades. Maintenance ketamine treatment—repeated doses over time—may help sustain the antidepressant benefit. A review of three randomized trials, eight open-label studies, and 30 case series found that intravenous, intranasal, oral, and possibly intramuscular and subcutaneous maintenance ketamine are effective for sustaining antidepressant effects in treatment-resistant depression. Serious side effects such as tolerance, cognitive problems, addiction, and kidney or urinary issues appear uncommon. Despite limitations in the available studies, maintenance ketamine shows therapeutic potential. More controlled and naturalistic long-term research is needed to clarify its role in routine care.
Frontiers in Neuroanatomy
March 18, 2022
Jurriaan F. M. Strous, C. Weeland, Femke A. van der Draai et al.
79 citations
Long-term recreational ketamine use is associated with lower gray matter volume, reduced white matter integrity, and decreased functional connectivity between brain regions, particularly thalamocortical and corticocortical pathways. A systematic review of 16 studies involving 440 chronic users (average 2.4 grams per day for 2–9.7 years) compared with 259 drug-free controls and 44 poly-drug controls found these neuroanatomical differences. The observed brain changes may help explain cognitive and psychiatric side effects of prolonged ketamine abuse, including memory impairment and executive functioning problems. The findings suggest that efforts to curb ketamine abuse are warranted given its potential long-term effects on the brain.
International Journal of Neuropsychopharmacology
June 25, 2021
J. Veraart, S. Smith-Apeldoorn, I. M. Bakker et al.
44 citations
Benzodiazepines and possibly lamotrigine reduce the antidepressant effects of ketamine, while lithium shows no significant interaction. Evidence from 24 studies indicates that clozapine, haloperidol, and risperidone interact with ketamine, though findings are mixed and based on low-quality evidence due to small sample sizes and varied methods. The review highlights the need for caution when combining ketamine with these drugs in psychiatric treatment.
Journal of Clinical Psychiatry
July 13, 2021
J. Veraart, S. Smith-Apeldoorn, J. Spijker et al.
31 citations
Ketamine is known to have rapid antidepressant effects, but patients with psychotic features are usually excluded from treatment studies due to concerns that ketamine might worsen psychosis. This systematic review examined nine reports (pilot studies and case reports) involving 41 patients with a history of psychosis or current psychotic symptoms who received ketamine for depression or negative symptoms. The findings suggest that short-term ketamine treatment can be both safe and effective in this group, with side effects that were mild and self-limiting. The available evidence does not support the assumption that ketamine exacerbates psychotic symptoms in predisposed patients, although data are limited and further trials are needed.