Effect of drug sample removal on prescribing in a family practice clinic

Little is known about the impact of recent restrictions on pharmaceutical industry detailing and sampling on prescribing behavior, particularly within smaller, independent practices. The objective of this study was to evaluate the effect of a policy prohibiting prescription drug samples and pharmaceutical industry interaction on prescribing patterns in a rural family practice clinic in central Oregon.

Segmented linear regression models were used to evaluate trends in prescribing using locally obtained pharmacy claims. Oregon Medicaid pharmacy claims were used to control for secular prescribing changes. Total and class-specific monthly trends in branded, promoted, and average prescription drug costs were analyzed 18 months before and after policy implementation.

Aggregate trends of brand name drug use did not change significantly after policy implementation. In aggregate, use of promoted agents decreased by 1.43% while nonpromoted branded agents increased by 3.04%. Branded drugs prescribed for respiratory disease declined significantly by 11.34% compared with a control group of prescribers. Relative to the control group, prescriptions of promoted cholesterol-lowering drugs and antidepressants were reduced by approximately 9.98% and 11.34%, respectively. The trend in average cost per prescription for lipid-lowering drugs was significantly reduced by $0.70 per prescription per month. Overall, average prescription drug costs increased by $5.18 immediately after policy implementation.

Restriction of pharmaceutical industry representatives and samples from a rural family practice clinic produced modest reductions in branded drug use that varied by class. Although aggregate average costs increased, prescriptions for branded and promoted lipid-lowering agents and antidepressants were reduced.