Bipolar depression is a leading cause of disability in the United States. Recently, N-methyl-D-asparate glutamate-receptor (NMDAR) antagonists, such as ketamine, have been shown to induce remission in bipolar depression. Nevertheless, ketamine use is limited by transient effects and psychogenic potential during repeated administration.
Kantrowitz, J. T., Halberstam, B., & Gangwisch, J. (2015). Single-Dose ketamine followed by daily D-Cycloserine in treatment-resistant bipolar depression. The Journal of clinical psychiatry, 76(6), 737-738. https://dx.doi.org/10.4088/JCP.14l09527
Link to full text