A Case Built on Current Research Findings
Ketamine has caused quite a stir in psychiatric practice. Sub-anesthetic administrations of ketamine have been shown to markedly improve symptoms of depression and anxiety.1 While the growing off-label use of ketamine speaks to the need for novel approaches to psychiatric care and treatment-resistant illness, it also presents an ethical dilemma, wherein widespread adoption has once again leaped ahead of scientific understanding.
The current literature suggests that therapeutic effects of ketamine involve modulation of glutamate neurotransmission, α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor potentiation, downstream influences on neurotrophic signaling cascades and neuroplasticity, and functional changes in assorted neural networks. Additional work is necessary to clarify the importance and reliability of these biological findings.
Another arc to the ketamine story dates back to a decades-old era of psychedelic research and search for medications with transformative power. Indeed, although primarily conceptualized today as a dissociative anesthetic, ketamine has also been classified more broadly as a hallucinogen. Hallucinogens function by various pharmacological mechanisms of action but exhibit similarities in their ability to occasion temporary but profound alterations of consciousness, involving acute changes in somatic, perceptual, cognitive, and affective processes.
Current biological theories involving ketamine’s antidepressant effect may be inseparable from these non-ordinary experiences of consciousness, but we can only know the answers to questions we ask. Here we examine findings from contemporary research that hint at the unexplored hallucinogenic potential of ketamine and considerations for future investigation.
Dr. Mathai is PGY 1 Psychiatry Resident, Dr. Mathew is Professor of Psychiatry, Dr. Storch is Professor of Psychiatry, and Dr. Kosten is Professor of Psychiatry, Baylor College of Medicine, Houston, TX.
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