Over several decades, research has shown that ketamine has antidepressive properties. Ketamine is approved by the U.S. Food and Drug Administration (FDA) as an anesthetic, although it is also being used for the management of psychiatric disorders and chronic pain management. Ketamine has been incorporated into the treatment of psychiatric disorders, such as major depressive disorder (MDD), bipolar disorder, and post-traumatic stress disorder (PTSD), as well as post-operative and chronic pain management. Ketamine infusion therapy is not a first-line therapy for psychiatric disorders or chronic pain management and may be considered by the patient’s interdisciplinary team after failure of standard treatment.
Ketamine infusion therapy involves the administration of a single infusion or a series of infusions for the management of psychiatric disorders like major depressive disorder, post-traumatic stress disorder, acute suicidality. Ketamine is a noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist that has traditionally been used for the induction and maintenance of anesthesia.
It’s not entirely clear how ketamine works. Because it exerts an antidepressant effect through a new mechanism, ketamine may be able to help people successfully manage depression when other treatments have not worked.
One likely target for ketamine is NMDA receptors in the brain. By binding to these receptors, ketamine appears to increase the amount of a neurotransmitter called glutamate in the spaces between neurons. Glutamate then activates connections in another receptor, called the AMPA receptor. Together, the initial blockade of NMDA receptors and activation of AMPA receptors lead to the release of other molecules that help neurons communicate with each other along new pathways. Known as synaptogenesis, this process likely affects mood, thought patterns, and cognition.
Ketamine also may influence depression in other ways. For example, it might reduce signals involved in inflammation, which has been linked to mood disorders, or facilitate communication within specific areas in the brain. Most likely, ketamine works in several ways at the same time, many of which are being studied.
Because ketamine is not FDA-approved for the treatment of depression, it is not covered by insurance and requires an out-of-pocket payment.