^ abcHimmelseher S, Pfenninger E (December 1998). "[The clinical use of S-(+)-ketamine--a determination of its place]". Anästhesiologie, Intensivmedizin, Notfallmedizin, Schmerztherapie. 33 (12): 764–70. doi:10.1055/s-2007-994851. PMID9893910
^“[The clinical use of S-(+)-ketamine--a determination of its place]”. Anästhesiologie, Intensivmedizin, Notfallmedizin, Schmerztherapie33 (12): 764–70. (December 1998). doi:10.1055/s-2007-994851. PMID9893910.
^“Synthesizing the Evidence for Ketamine and Esketamine in Treatment-Resistant Depression: An International Expert Opinion on the Available Evidence and Implementation”. Am J Psychiatry178 (5): 383–399. (May 2021). doi:10.1176/appi.ajp.2020.20081251. PMC9635017. PMID33726522. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9635017/. "A legitimate criticism, as it relates to interpreting the effect sizes reported with single or repeat-dose ketamine in TRD, is the possibility that nonspecific effects such as functional unblinding (e.g., by patients experiencing dissociation or euphoric responses) and expectancymayinadvertentlyinflate the efficacy of ketamine (51, 52). [...] Given the absence of an adequately designed head-to-head trial, the relative efficacies of intranasal esketamine and intravenous racemic ketamine are not known (65). [...] A recent meta-analysis comparing intranasal and intravenous ketamine formulations was unable to identify a significant difference between formulations as well as routes of delivery in efficacy at 24 hours, 7 days, and 28 days (17). A separate meta-analysis concluded that intravenous ketamine may be superior in efficacy and have lower dropout rates (66). However, it is difficult to draw definitive conclusions from these analyses given the heterogeneity across component studies."
^“Antidepressant Efficacy and Tolerability of Ketamine and Esketamine: A Critical Review”. CNS Drugs32 (5): 411–420. (May 2018). doi:10.1007/s40263-018-0519-3. PMID29736744. "In brief, these studies (Table 1) have globally assessed responses to a single dose of intravenous ketamine in 166 patients with TDR with multiple treatment failures, including electroconvulsive therapy (ECT). The findings provide evidence of improvement in depressive symptoms within hours, with a response rate > 60% in the first 4.5 and 24 h, and > 40% after 7 days, with a big effect size in comparison with placebo (Cohen's d 1.3–1.7) or active placebo (midazolam, d = 0.8). These figures, though preliminary, contrast with the average effect size of conventional antidepressants (Cohen's d 0.53–0.81 in patients with intense symptoms) [32] and their response latency (about 4–7 weeks) [1]."
^“Ketamine treatment for depression: opportunities for clinical innovation and ethical foresight”. Lancet Psychiatry4 (5): 419–426. (May 2017). doi:10.1016/S2215-0366(17)30102-5. hdl:10871/30208. PMID28395988. "Ketamine has been hailed as the most important advance in the treatment of depression of the past 50 years.1"