Prescribing rationale and budgetary outcomes associated with the introduction of a combined formulation of diclofenac sodium and misoprostol in Canada.

The budgetary impact of prescribing a combined formulation of diclofenac sodium and misoprostol to patients previously using nonsteroidal anti-inflammatory agents (NSAIDs), cytoprotective agents, or a combination of agents from both therapeutic categories is assessed, as is the clinical rationale for prescribing the combined formulation. Analysis of data for Canada on claims paid by third parties showed that the use of the combined formulation in Canada had resulted in significant initial overall savings and that the greatest cost savings were made for those who had previously used both an NSAID and a cytoprotective concomitantly. The inclusion of shadow costs (secondary costs) indicates that the use of the combined formulation over a 6-month period involves very low shadow costs (medical expenses related to ulcer treatment) compared with other NSAIDs: the shadow cost multiplication factor was 1.03 for the combined formulation compared with 1.22 to 3.47 for other NSAIDs. Pharmaceutical costs alone are insufficient for evaluating total budgetary impacts.