Aims: This study aimed to investigate acamprosate and naltrexone dispensing patterns in Australia.
Methods: A 10% representative sample of medications subsidized by the Australian Pharmaceutical Benefits Scheme (PBS) was used to identify individuals who were dispensed naltrexone or acamprosate between January 2006 and December 2023. Data were used to examine concurrent dispensing, medication switching and treatment episode length, as well as changes in prevalence and incidence over time.
Results: During the study, we identified 22 745 individuals with a total of 117 548 dispensed prescriptions (45.3% naltrexone, 43.0% acamprosate, and 11.7% concurrent dispensing). Alcohol pharmacotherapy dispensing occurred in 1354 per 100 000 individuals. It is estimated that 2.9% of individuals with an alcohol use disorder in Australia are receiving a PBS-listed pharmacological treatment. For both pharmacotherapies, individuals were most likely to be male (60.0%) and 35-54 years of age (56.0%). Individuals were more likely to switch from acamprosate to naltrexone rather than the reverse. From 2006 and 2023, the number of prevalent individuals treated with an alcohol pharmacotherapy significantly increased, driven mainly the use of naltrexone, which more than doubled over the study period. Incident naltrexone-treated individuals were more likely to remain on treatment for the recommended minimum 3-month period compared to acamprosate treated individuals, although overall dispensing for at least 3 months was low (5.1%).
Conclusions: In Australia between 2006 and 2023, rates of naltrexone dispensing have substantially increased, while acamprosate dispensing showed minimal changes. However, the use of alcohol pharmacotherapies remains low compared with the likely prevalence of alcohol use disorders.