Ketamine for the treatment of mental health and substance use disorders : comprehensive systematic review

Background

In the past twodecades,subanaestheticdosesofketaminehave been demonstrated to have rapid and sustained antidepressant effects, and accumulating research has demonstrated ketamine’s therapeutic effects for a range of psychiatric conditions.

Aims

In light of these findings surrounding ketamine’s psychotherapeutic potential, we systematically review the extant evidence on ketamine’s effects in treating mental health disorders.

Method

The systematic review protocol was registered in PROSPERO (identifier CRD42019130636). Human studies investigating the therapeutic effects of ketaminein the treatment ofmentalhealth disorders were included. Because of the extensive research in depression, bipolar disorder and suicidal ideation, only systematic reviews and meta-analyses were included. We searched Medline and PsycINFO on 21 October 2020. Risk-of-bias analysis was assessed with the Cochrane Risk of Bias tools and A Measurement Tool to Assess Systematic Reviews (AMSTAR) Checklist.

Results

We included 83 published reports in the final review: 33 systematic reviews, 29 randomised controlled trials, two randomised trials without placebo, three non-randomised trials with controls, six open-label trials and ten retrospective reviews. The results were presented via narrative synthesis.

Conclusions

Systematic reviews and meta-analyses provide support for robust, rapid and transient antidepressant and anti-suicidal effects of ketamine. Evidence for other indications is less robust, but suggests similarly positive and short-lived effects. The conclusions should be interpreted with caution because of the high risk of bias of included studies. Optimal dosing, modes of administration and the most effective forms of adjunctive psychotherapeutic support should be examined further.