Delays in Adopting Evidence-Based Dosages of Conventional Antipsychotics

By the 1980s, strong research evidence had emerged supporting the use of moderate doses of conventional antipsychotics—between 300 and 1,000 mg of chlorpromazine equivalent daily. We conducted a cross-sectional study of dosages of antipsychotics prescribed for 936 veterans with schizophrenia in 14 facilities between 1991 and 1995. Only 52 percent of these patients received prescriptions for recommended dosages; dosages were below the recommended range for 20 percent and above the range for 28 percent. African Americans were more likely than others to have received high dosages. These data suggest that there was considerable delay in the adoption of evidence-based dosing of conventional antipsychotics. Efforts must be made to transfer research findings more rapidly into practice.