Ketamine: 50 Years of Modulating the Mind

Summary & key facts

Ketamine is a medicine first used in the 1960s. Scientists still study it because it acts in many different ways on the brain and we do not fully understand all of them. Researchers have used ketamine to learn how general anesthesia works, and evidence suggests it may cause loss of consciousness by interrupting signals that go from the front of the brain to the back. Ketamine is useful in hospitals because it calms patients, eases pain, and tends to keep the heart and lungs stable. New research also suggests it might help people with hard-to-treat depression and Post-Traumatic Stress Disorder, but that idea is still being tested.

Key facts:

• Ketamine has been used in medicine since the 1960s and is still important in hospitals today.
• Researchers say ketamine affects many different targets in the brain, and its full effects are not yet fully understood.
• Scientists have used ketamine to study how anesthesia works and found it may block top-down signals from the front of the brain to the back, which could explain how it causes loss of consciousness.
• Ketamine is valued in anesthesiology and critical care because it can sedate patients and reduce pain while helping keep breathing and heart function stable.
• There is emerging evidence that ketamine might help treat people with severe, treatment-resistant depression and with Post-Traumatic Stress Disorder, but this use is still being researched and is not settled.
• The article reviewed ketamine’s history, how it acts on the brain, possible mechanisms, and the medical uses being studied now.

Abstract

Ketamine was introduced into clinical practice in the 1960s and continues to be both clinically useful and scientifically fascinating. With considerably diverse molecular targets and neurophysiological properties, ketamine's effects on the central nervous system remain incompletely understood. Investigators have leveraged the unique characteristics of ketamine to explore the invariant, fundamental mechanisms of anesthetic action. Emerging evidence indicates that ketamine-mediated anesthesia may occur via disruption of corticocortical information transfer in a frontal-to-parietal ("top down") distribution. This proposed mechanism of general anesthesia has since been demonstrated with anesthetics in other pharmacological classes as well. Ketamine remains invaluable to the fields of anesthesiology and critical care medicine, in large part due to its ability to maintain cardiorespiratory stability while providing effective sedation and analgesia. Furthermore, there may be an emerging role for ketamine in treatment of refractory depression and Post-Traumatic Stress Disorder. In this article, we review the history of ketamine, its pharmacology, putative mechanisms of action and current clinical applications.

Topics

Neuroscience and Neuropharmacology Research Treatment of Major Depression Tryptophan and brain disorders

Categories

Health Sciences Medicine Pharmacology

Tags

Cognitive science Ketamine Neuroscience Psychology

Substances

Ketamine

Conditions & symptoms

Chronic Pain Depression PTSD Chronic pain Sadness or low mood