Anxiety and PTSD
Anxiety and PTSD: what ketamine can and cannot do
The research is real, and it is mixed. Several controlled trials show rapid relief from anxiety and trauma symptoms; others do not. Here is what the evidence shows, and how we decide whether RESTORE is right for you.
Anxiety
What the research shows for anxiety
Anxiety disorders are common, and for many people the usual treatments, medication and therapy, do not bring enough relief. Ketamine acts on a different brain system, glutamate, and it has now been studied both in controlled trials and in thousands of patients treated in everyday practice.
In a placebo-controlled trial in social anxiety disorder, a third of patients responded after a single ketamine infusion, compared with none after placebo [1]. In people with treatment-resistant generalized and social anxiety who were not depressed, single doses eased anxiety within an hour, and the effect lasted up to a week [2]. A 2023 analysis pooling 14 controlled trials found anxiety reduced within hours of a single dose and still lower one to two weeks later [3].
One dose is not a course of treatment. Most of those trials tested a single infusion, so they show how quickly ketamine can work, not how long a full course lasts. When patients who had responded were treated weekly for three months, 18 of the 20 reported better social or work functioning [4]. Among 2,758 patients given a series of four to eight IV infusions at ten U.S. clinics, average anxiety scores fell from the severe range to the mild range, and nearly half met the study’s response threshold [5]. In a second clinic network, anxiety scores halved over treatment, and with maintenance the improvement held for more than seven months [6]. And in depression with prominent anxiety, which usually responds poorly to standard antidepressants, ketamine worked as well as in depression without anxiety in a controlled trial [7].
In our own practice, patients whose anxiety improved after a full course have generally kept that improvement about as long as our depression patients. That is our clinical experience, not a controlled trial.
The limits are real too. The real-world studies have no comparison group, and many patients did not finish treatment, which can make results look better than they are. The controlled trials are small, and one broader analysis found the overall effect on anxiety fell just short of statistical significance [8]. Ketamine is not FDA-approved for anxiety, and it is not a first treatment to try.
PTSD
What the research shows for PTSD
Few medicines work well for PTSD. The studies that gave ketamine as a full course, rather than a single dose, show the clearest benefit.
In a Mount Sinai trial of six infusions over two weeks, 67% of patients responded, compared with 20% given an active placebo [9]. In a 2025 controlled trial, 64% to 81% of patients responded within a day, depending on the dose, compared with 18% given an active comparator [10].
Studies without a placebo group, which are closer to everyday practice, report larger numbers still. In veterans with both PTSD and treatment-resistant depression, a course of six infusions was followed by PTSD remission in 80% [11]. Among more than 8,000 patients treated with IV ketamine in community clinics, 77% showed a meaningful drop in PTSD symptoms within six treatments, including patients without depression [12]. When a course of infusions was combined with a brief trauma-focused therapy, PTSD symptoms fell by half on average, and every patient who responded was still responding at last follow-up, up to six months later [13].
The limits: studies without a comparison group cannot separate the effect of ketamine from expectation and attention. The largest placebo-controlled trial, in 158 veterans and service members given eight infusions over four weeks, found no significant difference from placebo on PTSD symptoms overall, although depression improved [14], and a 2024 review of the controlled trials found the advantage over placebo small and short-lived [15].
Our reading: for many people with PTSD, especially those who also have depression, a full course of ketamine produces real, measurable improvement, and pairing it with trauma-focused therapy appears to help that improvement last. It is not yet an established PTSD treatment, which is why we measure every patient before and after.
What we actually do
Measure first, then decide with you
Anxiety and trauma symptoms rarely come alone. Most people who ask us about them also have depression, and that is where the evidence for ketamine is strongest.
Before you are accepted, we review your records in detail and measure where you stand on validated scales for depression, anxiety and trauma symptoms. The same scales are repeated after treatment, so you and Dr. Grass can see what changed.
RESTORE treats the depression, and anxiety and trauma symptoms often ease alongside it. Most people who respond notice a change within the first three days.
We tell you plainly what the evidence does and does not support for you, before you travel or pay. If other treatments have not helped and we believe ketamine is reasonable to try, we explain the uncertainty and measure the result. If we do not, we say so.
Before you decide
What to know if you have a trauma history
Trauma is part of many of our patients’ stories, and it shapes how we prepare you, how the infusion is run, and what happens afterward.
What the infusion can feel like. Most people feel detached or dreamlike during an infusion. For some people with trauma, that state can bring up difficult memories or emotions. It usually passes as the infusion ends.
You are prepared beforehand. Before your first infusion we talk through your history, what you might experience, and how we will respond, so that nothing comes as a surprise.
You are not alone in the room. Dr. Grass stays with you for the whole infusion and can slow or adjust it at any point if what you are feeling becomes too much.
Afterward. The days after treatment are a natural time to talk with your therapist about what came up. With your permission, we share the scores we measured, so your care continues where it belongs.
Your psychiatrist or therapist is part of the plan.
The people who already know you are an important part of your treatment. With your permission, we work with your psychiatrist or therapist before, during and after your course. Ketamine is added to that care. It does not replace it.
References
[1] Taylor JH, Landeros-Weisenberger A, Coughlin C, et al. Ketamine for social anxiety disorder: a randomized, placebo-controlled crossover trial. Neuropsychopharmacology. 2018;43(2):325–333. doi:10.1038/npp.2017.194
[2] Glue P, Neehoff S, Sabadel A, et al. Effects of ketamine in patients with treatment-refractory generalized anxiety and social anxiety disorders: exploratory double-blind psychoactive-controlled replication study. J Psychopharmacol. 2020;34(3):267–272. doi:10.1177/0269881119874457
[3] Hartland H, Mahdavi K, Jelen LA, et al. A transdiagnostic systematic review and meta-analysis of ketamine’s anxiolytic effects. J Psychopharmacol. 2023;37(8):764–774. doi:10.1177/02698811231161627
[4] Glue P, Neehoff SM, Medlicott NJ, et al. Safety and efficacy of maintenance ketamine treatment in patients with treatment-refractory generalised anxiety and social anxiety disorders. J Psychopharmacol. 2018;32(6):663–667. doi:10.1177/0269881118762073
[5] Hietamies TM, McInnes LA, Klise AJ, et al. The effects of ketamine on symptoms of depression and anxiety in real-world care settings: a retrospective controlled analysis. J Affect Disord. 2023. Retrospective records analysis.
[6] Ahuja S, Brendle M, Smart L, et al. Real-world depression, anxiety and safety outcomes of intramuscular ketamine treatment: a retrospective descriptive cohort study. BMC Psychiatry. 2022;22:634. doi:10.1186/s12888-022-04268-5. No control group.
[7] Salloum NC, Fava M, Freeman MP, et al. Efficacy of intravenous ketamine treatment in anxious versus nonanxious unipolar treatment-resistant depression. Depress Anxiety. 2019;36(3):235–243. doi:10.1002/da.22875
[8] Marchi M, Magarini FM, Galli G, et al. The effect of ketamine on cognition, anxiety, and social functioning in adults with psychiatric disorders: a systematic review and meta-analysis. Front Neurosci. 2022;16:1011103. doi:10.3389/fnins.2022.1011103
[9] Feder A, Costi S, Rutter SB, et al. A randomized controlled trial of repeated ketamine administration for chronic posttraumatic stress disorder. Am J Psychiatry. 2021;178(2):193–202. PMID 33397139
[10] Beaglehole B, et al. Ketamine for treatment-resistant post-traumatic stress disorder: double-blind active-controlled randomised crossover study. BJPsych Open. 2025. doi:10.1192/bjo.2025.10854
[11] Albott CS, Lim KO, Forbes MK, et al. Efficacy, safety, and durability of repeated ketamine infusions for comorbid posttraumatic stress disorder and treatment-resistant depression. J Clin Psychiatry. 2018;79(3):17m11634. Open-label, no control group.
[12] McInnes LA, Berman RM, Worley M, Shih E. A retrospective analysis of ketamine intravenous therapy for post-traumatic stress disorder in real-world care settings. Psychiatry Res. 2025;352:116689. doi:10.1016/j.psychres.2025.116689. Retrospective records analysis, funded by the company that holds the records.
[13] Feder A, Brown O, Rutter SB, et al. Combining ketamine infusions and written exposure therapy for chronic PTSD: an open-label trial. J Clin Psychiatry. 2025;86(2):24m15622. Open-label, no control group.
[14] Abdallah CG, Roache JD, Gueorguieva R, et al. Dose-related effects of ketamine for antidepressant-resistant symptoms of posttraumatic stress disorder in veterans and active duty military. Neuropsychopharmacology. 2022;47(8):1574–1581. doi:10.1038/s41386-022-01266-9
[15] Borgogna NC, Owen T, Vaughn J, et al. So how special is special K? A systematic review and meta-analysis of ketamine for PTSD RCTs. Eur J Psychotraumatol. 2024;15(1):2299124. doi:10.1080/20008066.2023.2299124
Ketamine is FDA-approved as an anesthetic. Its use for anxiety and PTSD is off-label.
Related pages
Depression and mood Are You a Candidate? Safety, Risks and Limits Fees
Talk to us
Ask whether it is reasonable for you
A short call is enough to tell you whether you are likely to be a candidate, before you travel or pay anything.
RESTORE — ketamine therapy, done precisely.