Skip to content

Real-world depression, anxiety and safety outcomes of intramuscular ketamine treatment: a retrospective descriptive cohort study

S. Ahuja, Madeline Brendle, Leo Smart, C. Moore, Paul Thielking, Reid Robison

BMC Psychiatry October 3, 2022 DOI: 10.1186/s12888-022-04268-5 (opens in new tab)

Study at a glance

AI-extracted from the abstract
Characteristics Retrospective cohort study Peer reviewed
Sample size 452
Population Adults with any psychiatric diagnosis receiving IM ketamine at a private outpatient psychiatric clinic network in the United States
Intervention Ketamine
Duration January 2018 to June 2021; maintenance improvements maintained for over 7 months
Measures PHQ-9, GAD-7
Topics Anxiety Depression Esketamine Ketamine
Key findings IM ketamine treatment was associated with significant improvements in depression and anxiety scores, with median PHQ-9 improving 38% and median GAD-7 improving 50%, and these improvements were maintained for over seven months. Adverse events occurred in 2.3% of treatments.

Abstract

Background: Ketamine has emerged as a promising pharmacotherapy for depression and other mental illnesses, and the intramuscular (IM) administration of ketamine is now offered at many North American outpatient psychiatric clinics. However, a characterization of the outpatient population receiving IM ketamine treatment and an evaluation of the real-world depression, anxiety, and safety outcomes of long-term psychiatric IM ketamine treatment has not been reported. This study aimed to evaluate the clinical characteristics, treatment patterns, clinical outcomes, and adverse events of patients receiving IM ketamine treatment.

Methods: Patient data from the electronic health records of a private outpatient psychiatric clinic network in the United States were collected and analyzed retrospectively. Adults with any psychiatric diagnosis who received ketamine treatment only by IM administration from January 2018 to June 2021 were included. A total of 452 patients were included in the cohort.

Results: Patients receiving IM ketamine treatment had a mean of 2.8 (SD 1.4) psychiatric diagnoses. 420 (93%) patients had a diagnosis of major depressive disorder, 243 (54%) patients had a diagnosis of generalized anxiety disorder, and 126 (28%) patients had a diagnosis of post-traumatic stress disorder. Patients received a median of 4 (range 1–48) IM ketamine treatments. Median depression scores (PHQ-9) improved 38% from 16.0 (IQR 11.3–21.8) at baseline to 10.0 (IQR 6.0–15.0) at last treatment ( p < .001). Median anxiety scores (GAD-7) improved 50% from 14.0 (IQR 8.0–17.0) at baseline to 7.0 (IQR 4.3–11.8) at last treatment ( p < .001). With maintenance ketamine treatments, average improvements in depression (PHQ-9) and anxiety (GAD-7) scores of at least 4.7 and 4.9 points were maintained for over 7 months. An adverse event occurred during 59 of 2532 treatments (2.3%).

Conclusions: IM ketamine is being utilized to treat psychiatric outpatients with multiple mental illnesses not limited to depression. Average depression and anxiety levels significantly improve throughout IM ketamine treatment and do not regress to baseline during patients’ maintenance treatment phase. Prospective studies are recommended to confirm the long-term effectiveness and safety of IM ketamine.

Comparable studies

Other observational and cohort studies on ketamine for anxiety, most cited first.

Study Year Design Participants
Treating bipolar depression with esketamine: Safety and effectiveness data from a naturalistic multicentric study on esketamine in bipolar versus unipolar treatment‐resistant depression Patients with treatment-resistant bipolar depression (B-TRD) and unipolar... 2023 Observational cohort n = 70
The effectiveness of ketamine on anxiety, irritability, and agitation: Implications for treating mixed features in adults with major depressive or bipolar disorder Adults with treatment-resistant major depressive disorder or bipolar disorder 2020 Retrospective analysis n = 201
At-home, sublingual ketamine telehealth is a safe and effective treatment for moderate to severe anxiety and depression: Findings from a large, prospective, open-label effectiveness trial. Outpatients receiving at-home ketamine-assisted therapy 2022 Prospective study n = 1,247
Predicting outcome with Intranasal Esketamine treatment: A machine-learning, three-month study in Treatment-Resistant Depression (ESK-LEARNING) Treatment-resistant depression patients 2023 Retrospective, multicentric, real-world study n = 149
Esketamine in treatment-resistant depression patients comorbid with substance-use disorder: A viewpoint on its safety and effectiveness in a subsample of patients from the REAL-ESK study Patients with treatment-resistant depression and a substance use disorder 2023 Observational, retrospective, multicentre study n = 26

Explore topics

By condition and practice