Effects of changes in patient cost sharing and drug sample policies on prescription drug costs and utilization in a safety-net-provider setting.

PURPOSE: The impact of cost-containment strategies on prescription drug utilization and costs in an ambulatory care safety-net-provider setting was studied, along with the impact of these strategies on patient out-of-pocket expenditures.
METHODS: Aggregate monthly prescription drug cost and utilization data were obtained from a health system's outpatient pharmacy computer system for the targeted clinic. The data represented approximately 42,000 patient visits over 38 months. Univariate and multivariate statistics were used to evaluate the influence of copayment increases and changes in prescription drug sample policies on prescription drug costs, prescription drug utilization, and patient expenditures.
RESULTS: Prescription drug copayment increases were associated with significant decreases in prescription drug utilization and costs. An average per visit prescription drug copayment increase of $5 was associated with a significant reduction in prescription drug utilization per visit and a $26.07 reduction in prescription drug expenditures per visit per month. Removal of samples from the clinic did not result in a significant decrease in either prescription drug costs or utilization. The presence of samples, however, was associated with a significant reduction in per visit patient expenditures by an amount similar to the copayment for one brand-name prescription drug per visit.
CONCLUSION: An increase in patient copayments was associated with reductions in a clinic's drug expenditures and prescription drug utilization per visit. Removal of prescription drug samples had no effect except increasing patients' out-of-pocket drug costs.