(R,S)-ketamine (ketamine) exerts rapid (within hours) and robust (>60% response) antidepressant effects in severely ill-depressed patients who have failed conventional treatments (Zarate et al, 2006). This clinical finding has been paradigm-shifting as there is now tremendous hope that very ill-depressed patients can be treated in a matter of hours, rather than many weeks or months required for standard therapies to take effect (if they do at all).
Gould, T. D., Zanos, P., & Zarate, C. A. (2017). Ketamine Mechanism of Action: Separating the Wheat from the Chaff. Neuropsychopharmacology, 42(1), 368-369. 10.1038/npp.2016.210
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