Recent trends in antipsychotic combination therapy of schizophrenia and schizoaffective disorder: implications for state mental health policy.

Little is known about antipsychotic combination therapy, although this practice is becoming increasingly common in the treatment of schizophrenia. Medicaid pharmaceutical claims for a cohort of 836 New Hampshire beneficiaries with schizophrenia or schizoaffective disorder were followed from 1995 through 1999. Use of traditional and atypical antipsychotic medications, antidepressants, anxiolytic hypnotics, and mood stabilizers was tracked monthly. The number of medications, frequency of coprescription, and Medicaid pharmaceutical costs are described. The proportion of individuals with schizophrenia and schizoaffective disorder treated with atypical antipsychotics grew from 43 percent in 1995 to 70 percent in 1999. At the same time, concurrent use of two or more antipsychotic medications quadrupled, increasing from 5.7 percent to 24.3 percent. Persons with schizophrenia were also prescribed more antidepressants (increased from 18.5% in 1995 to 35.6% in 1999), anxiolytics (increased from 19.9% to 33.5%), and mood stabilizers (increased from 17.7% to 30.0%). The increase in multiple agent therapy appears to be broad-based. Data are needed on the effectiveness and cost-effectiveness of these practices to inform clinical decision making and health policy.