Ketamine, an NMDA receptor antagonist with dissociative properties, has demonstrated rapid antidepressant effects even in treatment-resistant cases — sometimes within hours of administration. Its clinical use for depression, suicidality, and chronic pain is expanding as the research base deepens, though the durability of effects and the role of the psychedelic experience in therapeutic outcomes remain active questions. Understanding ketamine requires distinguishing between its pharmacological mechanisms and the subjective experiences it produces, which may each contribute differently to healing.
Each step builds on the last.