Ketamine in the Treatment of Obsessive-Compulsive Disorder: A Systematic Review

Summary & key facts

Researchers reviewed nine studies that tested ketamine for obsessive-compulsive disorder (OCD). Some studies found that ketamine can reduce OCD symptoms quickly and people usually tolerated it, but the results were mixed and the evidence is small. Most studies gave a single intravenous dose of the usual mixed form of ketamine, and we still do not know which form, dose, or number of sessions works best. Bigger, carefully controlled studies are needed before doctors can know if ketamine should be used for OCD.

Key facts:

• This paper is a systematic review, which means the authors searched medical databases to find and summarize all studies on ketamine for OCD.
• The review included nine studies in total: three carefully controlled trials, three case reports of individual patients, two open studies without placebo controls, and one chart review of past patient records.
• Some studies reported that ketamine could reduce OCD symptoms quickly after treatment and that most people tolerated the drug without major problems.
• The results across studies were inconsistent, meaning some people improved but others did not, and the size and duration of benefit varied.
• Most studies used a single intravenous (given into a vein) dose of racemic ketamine, which is the common mix of the drug’s two mirror-image forms.
• There is no clear evidence yet comparing the mixed form of ketamine to its separate mirror-image forms (called S-ketamine and R-ketamine) for treating OCD.
• Only a few reports looked at pairing ketamine with psychotherapy, and that idea has only very limited support so far.
• The authors say we need larger, randomized, double-blind, placebo-controlled trials — that is, bigger and more carefully designed studies where people are randomly given either ketamine or a fake treatment and neither they nor the researchers know who got which — to learn the best way to use ketamine for OCD.

Abstract

INTRODUCTION: First-line treatment for obsessive-compulsive disorder (OCD) includes exposure and response prevention behavioral therapy and serotonin reuptake inhibitors, particularly in combination. New and more effective treatments are needed, give that recent studies suggest that glutamatergic neurotransmission contributes to the pathophysiology of the disorder. In these circumstances, ketamine, as a potent N-methyl-D-aspartate receptor antagonist and glutamate modulator, offers alternative possibilities for OCD treatment. METHODS: This systematic review aims to investigate the effects of ketamine in OCD, following the Preferred Reporting Items for Systematic Review and Meta-analyses Protocols (PRISMA-P). Searches were carried out using the PubMed/MEDLINE, Embase, and PsycINFO databases. RESULTS: Nine articles were included, of which three were randomized controlled trials, three case reports, two open-label trials, and one a retrospective chart review. Reported data have shown a potential for fast onset of action and good tolerability of ketamine for OCD, even though the principal studies used only single-session racemic ketamine treatments, administered intravenously, and the results have been erratic. In addition, none of the available evidence demonstrates whether racemic ketamine, S-ketamine, or R-ketamine has the best efficacy in controlling OCD symptoms, and only sparse evidence suggests that a combination of ketamine and psychotherapy could benefit patients with OCD. CONCLUSION: In order to advance clinical practice regarding the use of ketamine in treating OCD, future randomized, double-blind, placebo-controlled trials are required. These trials need to use larger samples to explore ketamine and its enantiomers, with different methods of administration, multiple sessions, and appropriate washout periods.

Topics

Body Image and Dysmorphia Studies Obsessive-Compulsive Spectrum Disorders Treatment of Major Depression

Categories

Clinical Psychology Psychology Social Sciences

Tags

Adverse effect Alternative medicine Clinical trial Dissociative Internal medicine Ketamine Law Medicine MEDLINE Meta-analysis Pathology Pharmacology Placebo Political science Psychiatry Psychology PsycINFO Randomized controlled trial Systematic review Tolerability

Substances

Ketamine

Conditions & symptoms

Obsessive-Compulsive Disorder Anxiety or worry