Definition
A dissociative anesthetic developed in the 1960s, now used at sub-anesthetic doses for treatment-resistant depression and other mental health conditions.
In Depth
Ketamine is an NMDA-receptor antagonist with rapid-acting antidepressant effects. Originally introduced as a surgical anesthetic, it is now used off-label by psychiatrists at sub-anesthetic doses for depression, PTSD, anxiety, and pain.
The (S)-enantiomer (esketamine) is FDA-approved as Spravato (intranasal) for treatment-resistant depression. Racemic ketamine is also used off-label via IV, IM, or oral routes in clinical practice.
Related Terms
Esketamine
The (S)-enantiomer of ketamine, FDA-approved as the nasal spray Spravato for treatment-resistant depression and depressive symptoms in adults with major depressive disorder with acute suicidal ideation or behavior.
Ketamine-Assisted Therapy
A clinical protocol in which sub-anesthetic doses of ketamine are administered (IV, IM, oral, or intranasal) under medical supervision to treat depression, PTSD, anxiety, or chronic pain — typically combined with structured psychotherapy.
Spravato
Brand name for esketamine intranasal spray, manufactured by Janssen. FDA-approved in 2019 for treatment-resistant depression; administered only in certified clinics under a Risk Evaluation and Mitigation Strategy (REMS).
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