1. Abott CS, et al. “Efficacy, Safety, and Durability of Repeated Ketamine Infusions for Comorbid Posttraumatic Stress Disorder and Treatment-Resistant Depression” Journal of Clinical Psychiatry. 2018 May/Jun; 79(3).
SUMMARY: This study identified individuals with comorbid PTSD and major depressive disorder. They each received 6 intravenous ketamine infusions (0.5 mg/kg) on a Monday-Wednesday-Friday schedule over a 12-day period from May 2015 to June 2016. Data from outcome measures were collected before and 24 hours after each infusion and weekly for 8 weeks following the final infusion. The remission rate for PTSD was 80%, and the response rate for treatment-resistant depression was 93.3%. Participants in remission from PTSD after the infusion series (n = 12) had a median time to relapse of 41 days. Similarly, participants whose depression symptoms responded to the infusion series (n = 14) had a median time to relapse of 20 days. Repeated ketamine infusions were associated with transient increases in dissociative symptoms. No participant reported worsening of PTSD symptoms over the study duration. This study found rapid and sustained improvement in PTSD and depression symptoms. This report suggests that repeated ketamine treatments are safe and may represent an efficacious treatment for individuals with comorbid PTSD and treatment-resistant depression.
2. Feder, Parides, et al. “Efficacy of intravenous ketamine for treatment of chronic posttraumatic stress disorder: a randomized clinical trial” JAMA Psychiatry. 2014 Jun; 71(6): 681-8.
http://archpsyc.jamanetwork.com/article.aspx?articleid=1860851SUMMARY: In this double blind, placebo-controlled cross over study, a single dose of ketamine (.5mg/kg over 40 minutes) was compared to midazolam. Authors note a significant immediate reduction in the CAPS score and frequently this reduction was maintained for over 2 weeks. The only side effects noted were transient dissociative symptoms, none of which required stopping the infusion.
3. Liriano, Felix, et al. “Ketamine as treatment for post-traumatic stress disorder: a review” Drugs in Context.2019; 8: 212305.
SUMMARY: This article is a review of the current literature for the treatment of PTSD. Their findings were as follows: Based on the limited data in the form of animal studies, a randomized controlled trial, and case reports, ketamine has been shown to result in a near complete resolution of symptoms over the short term and seems to have similar findings to the use of ketamine in MDD. These clinical improvements are immediate and last well beyond the half-life of ketamine but unfortunately are transient lasting 1–2 weeks. It is thought that upregulating BDNF and antagonizing NMDA serve to reverse some of the damage caused by chronic stress. With more investigation, ketamine may prove to be a viable tool in treating PTSD for those who fail more conventional treatments.
4. Krystal JH, et al. “Synaptic Loss and the Pathophysiology of PTSD: Implications for Ketamine as a Prototype Novel Therapeutic” Curr Psychiatry Rep. 2017 Aug 26; 19(10): 74.
SUMMARY: This is a review of evidence that PTSD might be a “synaptic disconnection syndrome” and the evidence for the emerging therapeutic application of ketamine as a potential rapid-acting treatment for this disorder that may work, in part, by restoring synaptic connectivity. Synaptic disconnection may contribute to the profile of PTSD symptoms that may be targeted by novel pharmacotherapeutics.