Ketamine, via intravenous infusions, has emerged as a novel therapy for treatment-resistant depression, given rapid onset and demonstrable efficacy in both unipolar and bipolar depression. Duration of benefit, on the order of days, varies between these subtypes, but appears longer in unipolar depression. A unique property is reduction in suicidality although data are more limited. Strategies to extend duration, via multiple doses, maintenance treatment, or subsequent augmenting medications have yielded mixed results. There is a relative paucity of data regarding alternate methods of administration such as intramuscular, intranasal, and oral routes, though preliminary results are promising. Adverse effects most reliably include dissociative and sympathomimetic effects, both transient and mild, and suggest good tolerability. Ketamine’s unique effects may represent an opportunity for a paradigm shift in the pharmacologic treatment of depression.
Ryan, W. C., Marta, C. J., & Koek, R. J. (2014). Ketamine and depression: A review. International Journal of Transpersonal Studies, 33(2), 40-74.
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