Use of Antipsychotic Medications in Australian States and Territories Between July 1995 and December 2001

Objective: To examine trends in the use of oral conventional, depot and atypical antipsychotic medications in Australian States and Territories between 1995 and 2001. Methods: For each 6 month interval between July 1995 and December 2001, prescription data obtained were converted into a measure of drug utilization expressed as the number of defined daily doses per thousand population per day (DDDs/1000/day). Data concerning the major specialty of the prescriber were available for the period 1996–2000. Results: In each State and Territory, use of atypical antipsychotic medications increased markedly while use of oral conventional and depot medications declined. Between July 2001 and December 2001, the proportion of total prescriptions for antipsychotic medications accounted for by prescriptions for atypical medications varied from 63.1% in South Australia to 76.1% in the Australian Capital Territory (ACT). Relative use of atypical medications was higher in the ACT than in other regions, while relative use of depot medications was higher in the Northern Territory than in other regions. During the year 2000, the proportion of prescriptions for oral conventional and depot medications written by general practitioners (GPs) exceeded 75% in all regions other than the ACT. Between 1996 and 2000, the proportion of prescriptions for atypical medications written by GPs increased markedly in all regions but remained lower than for oral conventional and depot medications. Conclusions: Atypical antipsychotic medications have replaced conventional medications as the first-line pharmacological treatment for psychotic disorders in all regions of Australia. Continued expansion of programmes designed to foster collaboration between GPs and mental health services will be essential in achieving optimal prescribing of antipsychotic medications.