- The purposes of this paper were to examine the medication prescribing patterns for bipolar I disorder in hospital settings and to compare them to recently published expert consensus guidelines for medication treatment of bipolar disorder.Data were obtained from the 1996-2000 CQI+SM Outcomes Measurement System, on patients age 18 or older admitted to psychiatric inpatient units from over 100 medical-surgical hospitals. A total of 1864 patients with a primary discharge diagnosis of bipolar I or II disorder were identified from a large cohort of hospitalized patients. Patient characteristics were assessed at hospital admission and medication usage, at discharge. The medication analysis focused on the 1471 individuals with bipolar I mania or bipolar I depression (with or without psychotic features), representing 54% and 25% of admitted bipolar patients, respectively.At admission, the typical bipolar patient (mean age 57) had experienced a relatively severe and chronic course of illness. The array of psychotropic agents used was broad, with no single prescribing pattern predominant. Only one in three bipolar I (manic or depressed) patients with psychotic features was discharged on medications recommended by expert guidelines as preferred or alternate recommended treatment. Absent psychotic features, this dropped to one in six patients. Surprising was the relatively high use of antidepressants for patients with mania, particularly those without psychotic symptoms.Results suggest that a substantial proportion of patients with bipolar I disorder are discharged from hospitals on medications not generally recommended by current practice guidelines.