Uptake of COX-2 selective inhibitors and influence on NSAID prescribing in Northern Ireland.

Purpose: Rofecoxib and celecoxib have been recently introduced and promoted as 'safer' non-steroidal anti-inflammatory drugs (NSAIDs) regarding gastric toxicity. The primary aim was to measure their uptake and any impact on conventional NSAID prescribing. A secondary aim was to assess any change in proton pump inhibitor (PPI) prescribing.

Methods: Prescribing data in terms of defined daily doses (DDDs) were pooled from 1997 onwards. Linear trends in the data were tested for using regression analyses. Direct comparisons were made between the April-June quarter of the year 1999 (i.e. before the introduction of rofecoxib and celecoxib) and the same quarter 3 years later.

Results: Overall NSAID prescribing in Northern Ireland was found to be increasing linearly at an estimated rate of 154,000 DDDs per quarter since the introduction of celecoxib and rofecoxib. The rate of increase in the volume of prescribing of the two new drugs was found to be four times the rate of decrease in prescribing of the 'older' NSAIDs. Overall prescribing of anti-inflammatory agents had increased from 37.8 to 47.7 DDDs/1000 patients/day over 3 years with no effect on the upward trend in PPI prescribing.

Conclusions: The introduction of rofecoxib and celecoxib has increased prescribing volume of anti-inflammatory agents by 26% in Northern Ireland over the 3-year period. This could pose safety problems in the future as more people are being prescribed anti-inflammatory agents.