Skip to content

Temporal Immune Effects of Oral Ketamine on PTSD: Transcriptomic Evidence of Short-Term Inflammation Suppression and Long-Term Immune Remodelling

Nathan J Wellington, Bonnie L. Quigley, Ana P. Bouças, Megan Dutton, Adem T. Can, Jim Lagopoulos, Anna V. Kuballa

medRxiv Preprint Server May 26, 2025 preprint DOI: 10.1101/2025.05.26.25328370 (opens in new tab)

Study at a glance

AI-extracted from the abstract
Characteristics Observational cohort
Sample size 23
Population PTSD participants (9 males, 14 females)
Intervention Oral ketamine
Duration 6-week intervention; PBMCs collected at baseline, one week, and four weeks post oral ketamine
Topics Esketamine Ketamine PTSD
Keywords Ketamine therapy PTSD Treatment Mental health treatment Ketamine For PTSD Immunology Immune system Immune regulation Inflammation Anti-inflammatory Gene expression Gene activity Gene regulation Genomics Molecular mechanisms Personalized medicine Precision mental health Individualized therapy Tailored care
Key findings Ketamine induces a transition from short-term inflammation suppression and antimicrobial activity to long-term sustained immune regulation, inflammation remodulation, and tissue repair in PTSD patients.

Abstract

Ketamine’s rapid acting symptom relief make it a promising intervention for PTSD. However, the mechanisms driving its long-term efficacy over weeks and months remain poorly understood. This study investigated the short-and long-term impacts on gene expression of a six-week subanesthetic oral ketamine trial in 23 PTSD participants (9 males, 14 females). Peripheral Blood Mononuclear Cells (PBMCs) were collected at baseline, one week (short-term), and four weeks (long-term) post oral ketamine for RNA sequencing and transcriptome analysis. Differential expression analysis identified substantial and persistent transcriptomic changes over time, with 533 genes upregulated and 621 downregulated across timepoints. Notably, there was a 37% increase in differential gene expression between the short-and long-term responses, accompanied by a 6.5-fold rise in expression magnitude and an 8.8-fold enhancement in pathway activity. Pathway analysis emphasised critical immune and inflammatory pathways that appear to be modulated by ketamine, including interferon alpha/beta signalling (z = 4), IL-17 signalling pathway (z = 3.36), and cytokine storm signalling (z = 4.26), neutrophil degranulation (z = 6.0) and antimicrobial peptide signalling (z = 1.63) which differed across timepoints. The findings suggest a transition from short-term inflammation suppression and antimicrobial activity to long-term sustained immune regulation, inflammation remodulation and tissue repair. Key cytokines, chemokines, interferons and antimicrobial peptides included, IL-6, IL-1β, IFI27, IL-10 signalling, CXCL8, SOCS1/3 and CAMP which represent central regulators of immune and inflammatory pathways. These molecular changes offer novel insights into the short-and long-term therapeutic potential of ketamine for PTSD and highlight avenues for precision psychiatry and individualised maintenance therapy to prevent relapse.

Comparable studies

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

Study Year Design Participants
Impact of oral ketamine augmentation on hospital admissions in treatment-resistant depression and PTSD: a retrospective study. Outpatients with treatment-resistant depression and PTSD 2018 Retrospective review n = 37
Ketamine-Assisted Psychotherapy Provides Lasting and Effective Results in the Treatment of Depression, Anxiety, and Post-Traumatic Stress Disorder at 3 and 6 Months: Findings from a Large Retrospective Effectiveness Study. Adults with a history of major depressive disorder, generalized anxiety disorder, or... 2024 Retrospective effectiveness study n = 346
Combined ketamine and psychotherapy provide no additional benefit beyond ketamine alone in treating depression or PTSD: Evidence from a help-seeking sample. Help-seeking individuals with depression and/or PTSD 2025 Observational cohort n = 624
Rapid and sustained reduction of treatment-resistant PTSD symptoms after intravenous ketamine in a real-world, psychedelic paradigm. Outpatients with elevated PTSD Checklist for DSM-5 scores 2025 Retrospective study n = 117
Ketamine treatment effects on DNA methylation and Epigenetic Biomarkers of aging Individuals with major depressive disorder or posttraumatic stress disorder 2024 Observational cohort n = 20

Explore topics

By condition and practice