Antipsychotic dosing and concurrent psychotropic treatments for Medicaid-insured individuals with schizophrenia

Antipsychotic medications have been first line treatment for schizophrenia for half a century, yet few studies have assessed outpatient maintenance treatment in large populations. This article describes oral antipsychotic dosing patterns and psychotropic treatments using computerized Medicaid claims data for individuals who were diagnosed with schizophrenia and received treatment on an outpatient basis during 1991. The findings show that the mean daily oral antipsychotic dose was 729+/-586 chlorpromazine equivalents (CPZ-EQ) for high-potency agents and 304+/-328 CPZ-EQ for low-potency agents. Males, younger individuals, and African-Americans received larger mean daily doses of high-potency agents, ranging from 747 to 800 CPZ-EQ. Antiparkinsonian agents were prescribed for over 90 percent of the outpatient antipsychotic treatment exposure. In summary, young adults, males, and African-Americans were given high-potency antipsychotic medications at outpatient maintenance doses that exceeded the maximum recommended levels, despite well-established evidence that high-dose treatment offers no additional benefit. Likewise, concurrent antiparkinsonian treatment exceeded the 1990 World Health Organization recommendations.