Expenditure on healthcare in Ireland has increased from under €3.5 billion in 1997 to an estimated €11.9 billion in 2005. Pharmaceuticals account for approximately 11% of this expenditure. Within the Community Drug Schemes the GMS scheme accounts for approximately 75% of all prescription items and approximately 70% of the cost of medicines reimbursed by the HSE - Shared Services - Primary Care Reimbursement Service. Expenditure under medicines on the GMS scheme has doubled from €338 million to €763 million over the time period 2000 - 2004.The top 30 drugs of highest cost to the GMS in 2004 accounted for approximately 50% of the total GMS expenditure. The majority of the cost of prescriptions on the GMS are attributable to drugs relating to the cardiovascular system, alimentary tract and metabolism and the nervous system.