Potential Antidepressive Effects of R-ketamine in Patients with Treatment Resistance Depression
Carleton undergraduate journal of science. May 16, 2025 Sumika Egner
Ketamine, long used as an anesthetic, also reduces depressive symptoms at lower doses, especially in people with treatment-resistant depression (TRD) for whom standard antidepressants often fail. Pre-clinical studies of ketamine's two mirror-image forms—R-ketamine and S-ketamine—suggested that R-ketamine might work faster, last longer, and cause fewer side effects and less risk of abuse. However, early clinical trials testing R-ketamine for TRD have not yet shown clear antidepressant benefits, even though the drug appeared safe and tolerable. This review compares the two enantiomers and concludes that while R-ketamine looked promising in animal studies, it did not consistently reduce depression in human trials, making its effectiveness uncertain.