“Rapid cycling” in bipolar disorder is defined by the occurrence of at least 4 episodes of mania, hypomania, depression, or mixed states during the preceding 12 months. Episodes are demarcated by partial or full remission for at least 2 months or a switch to an episode of opposite polarity. In this podcast, Dr. Ross J. Baldessarini of McLean Hospital and Harvard Medical School discusses the prevalence of rapid cycling and the challenges in its treatment. Rapid cycling is more common in women and is associated with an elevated risk of suicide. Dr. Baldessarini's comments are informed by recent efforts he and his colleagues undertook to synthesize reviews and meta-analyses on prevalence rates and response rates to treatment, as well as on their recently research on a cohort of 1261 bipolar disorder patients with or without rapid cycling who were followed up for at least 1 year.   The March-April 2024 issue of the Journal of Clinical Psychopharmacology includes a commentary from Dr. Baldessarini, Dr. Alessandro Miola, Dr. Mark A. Frye,  and Dr. Leonardo Tondo titled “Current Status and Treatment of Rapid Cycling Bipolar Disorder.”