David J. Hellerstein, M.D., is a research psychiatrist at the New York State Psychiatric Institute and a Professor of Clinical Psychiatry at the Columbia University Irving Medical Center. He specializes in research and treatment of mood and anxiety disorders, particularly the medication treatment of chronic depression. His current studies include psilocybin in treatment-resistant depression and psilocybin for body dysmorphic disorder. Dr. Hellerstein is Director of the Depression Evaluation Service, which conducts studies on the medication and psychotherapy treatment of conditions including major depression, chronic depression, and bipolar disorder. He has published over 125 scientific articles and book chapters on subjects including the treatment of persistent depressive disorder. Dr. Hellerstein received his medical degree from Stanford University Medical School.