Case ReportsAugmentation Therapy With Serial Intravenous Ketamine Over 18 Months in a Patient With Treatment Resistant DepressionHassamal, Sameer MD*†; Spivey, Margaret NP*; Pandurangi, Ananda K. MD*Author Information *Department of Psychiatry, Virginia Commonwealth University, Richmond, VA; and †Department of Addiction Psychiatry, UCLA Kern, Bakersfield, CA. Address correspondence and reprint requests to Sameer Hassamal, MD, Department of Psychiatry VCU School of Medicine PO Box 980710 Richmond, VA 23298; E-mail: firstname.lastname@example.org Conflicts of Interest and Source of Funding: The authors have no conflicts of interest to declare. Clinical Neuropharmacology: September/October 2015 - Volume 38 - Issue 5 - p 212-216 doi: 10.1097/WNF.0000000000000104 Buy Metrics Abstract Major depressive disorder is a severe illness that affects 3% to 7% of adults annually in the United States. About 30% of these individuals are refractory to multiple treatment trials. Recent reports have found a significant and almost immediate improvement in depressive symptoms after single or multiple ketamine intravenous infusions (IVIs) in such patients. We present the case of A.B., a patient with treatment-resistant depression (TRD) including to subgenual deep brain stimulation, who went into remission after augmentation with 6 ketamine IVIs (0.5 mg/kg) over a 3-week period. However, she had a reemergence of depressive symptoms 4 months later and received a second series of 3 ketamine IVIs over the course of a week. A.B. again went into remission and maintained this for the next 8 months. At this time, she experienced a reemergence of depressive symptoms and was treated with the third series of ketamine IVIs (3 infusions over the course of a week). Because A.B. has now been in remission for 6 months. A.B. has received a total of 12 ketamine IVIs over the course of 18 months. No significant adverse events have occurred. To our knowledge, this is the first case of long-term ketamine efficacy as augmentation therapy in TRD over the course of 18 months. There is a need for studies examining the long-term management of TRD with IV ketamine. Guidelines for maintenance ketamine IVIs in TRD also need to be developed. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.