Average duration of treatment with antipsychotics among concession card holders in Australia

Objective:To analyse average treatment duration with antipsychotics reimbursed for concession card holders under the Pharmaceutical Benefits Scheme; the proportion of initial prescribing by general practitioners, psychiatrists and other physician; and the trend in drug choice in Australia.Method:Based on a representative 10% sample of patients receiving Pharmaceutical Benefits Scheme prescriptions since 2005, antipsychotics redeemed by concession card holders in the period from 2010 to 2013 were analysed. A 5-year baseline period was used to exclude prevalent users from incident users. Treatment duration was estimated using the epidemiological equation: prevalence/incidence = average duration.Results:The overall average treatment duration was 3.0 years, ranging from 1.5 years in patients aged 75 years and older to more than 4 years among patients aged 25–64 years. The most commonly used antipsychotics were olanzapine, risperidone and quetiapine, with average duration of 2.9, 2.1 and 1.7 years, respectivel...