Utilization of anti-Parkinson drugs in Australia: 1995-2009

To examine trends in the prescribing of anti-Parkinsonian drugs (APD) in Australia from 1995 to 2009.

We analyzed the Medicare Australia and Drug Utilisation Sub-Committee (DUSC) databases for prescription data for overall APD dispensed use from 1995. We were able to examine prescribing by gender, age, and type of prescriber between 2002 and 2009. Prescriptions were converted to defined daily doses (DDD)/1000 population/day using Australian Bureau of Statistics population data.

Dispensed use of levodopa + carbidopa remained steady from 1995 to 2009 (0.76-0.82 DDD/1000 population/day); levodopa + benserazide use increased from 0.34 to 0.55 DDD/1000 population/day. Since 2005 dispensed use of levodopa + carbidopa + entacapone has steadily increased, from 0.03 to 0.10 DDD/1000 population/day. In July 2009 levodopa + carbidopa was the most widely used agent, followed by levodopa + benserazide, then benztropine. Cabergoline increased from 1999, peaked in 2006, and thereafter declined. APD use peaked in males and females aged 60-69 years. Age-adjusted utilization was slightly higher in males than females.

The amount of levodopa dispensed has slowly increased with levodopa + benserazide increasing faster than levodopa + carbidopa. Use of cabergoline fell when pramipexole became available and the risk of ergot-related serosal adverse effects was more widely appreciated. Use of centrally acting anti-cholinergics decreased over a period of time when use of atypical anti-psychotic agents increased.