Background Depression and anxiety outcome measures, safety/tolerability, patient satisfaction, and ease of implementation of group-based ketamine-assisted psychotherapy (G-KAP) delivered to patients in intensive residential eating disorder (ED) treatment were assessed. Case presentation This study reports on five participants with a diagnosis of an ED and comorbid mood and anxiety disorders who received weekly intramuscular ketamine injections in a group setting over 4 weeks. Measures of anxiety (GAD-7) and depression (PHQ-9) were administered pre-dose, 4-h post-dose, and 24-h post dose. Four of the 5 participants experienced clinically significant improvements on the PHQ-9 score (i.e., change greater than 5) while 2 of the 5 participants experienced clinically significant improvements on the GAD-7 score (i.e., change greater than 4) from pre-dose to 24-h post-dose after the last ketamine session. Dosing sessions were well tolerated, and no serious adverse events were reported. Clinical observations and participant reports corroborated improvements in depression and anxiety symptoms, good tolerability of ketamine treatment, and practical implementation of the G-KAP protocol in a residential ED treatment center. Conclusions This study suggests the potential utility of G-KAP as an adjunct to intensive, specialized ED treatment. Overall, this novel, cross-diagnostic intervention warrants future research to further explore its appropriateness in a treatment setting.

Eating disorders (EDs) are serious, life-threatening psychiatric conditions associated with physical and psychosocial impairment, as well as high morbidity and mortality. Given the chronic refractory nature of EDs and the paucity of evidence-based treatments, there is a pressing need to identify novel approaches for this population. The noncompetitive N-methyl-D-aspartate receptor (NMDAr) antagonist, ketamine, has recently been approved for treatment-resistant depression, exerting rapid and robust antidepressant effects. It is now being investigated for several new indications, including obsessive–compulsive, post-traumatic, and substance use disorder, and shows transdiagnostic potential for EDs, particularly among clinical nonresponders. Hence, the aim of this review is to examine contemporary findings on the treatment of EDs with ketamine, whether used as a primary, adjunctive, or combination psychopharmacotherapy. Avenues for future research are also discussed. Overall, results are encouraging and point to therapeutic value; however, are limited to case series and reports on anorexia nervosa. Further empirical research is thus needed to explore ketamine efficacy across ED subgroups, establish safety profiles and optimize dosing, and develop theory-driven, targeted treatment strategies at the individual patient level.

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.

Aim: There is limited real-world evidence for patients with treatment-resistant depression (TRD) receiving esketamine nasal spray. Methods: This retrospective cohort study used data collected from a psychiatric clinic's EHR system. Results: A total of 171 TRD patients received esketamine July 2019–June 2021. This predominantly female, white population had several mental health comorbidities and high exposure to psychiatric medications. We observed significant reductions (p < 0.001) in average PHQ-9 and GAD-7 scores from baseline (PHQ-9: mean: 16.7; SD: 5.8; GAD-7: mean: 12.0; SD: 5.8) to last available treatment (PHQ-9: mean: 12.0; SD: 6.4; GAD-7: mean: 8.7; SD: 5.6). There were no reports of serious adverse events. Conclusion: This study found a significant disease burden for patients with TRD. Esketamine appears to be well tolerated and effective in improving depression and anxiety.