Drug product selection in Illinois: the first year's experience.

This paper reports an evaluation of Illinois' drug product selection (DPS) law. The results show that while consumers saved an average of $1.47 whenever DPS occurred in the study period, the prescription format mandated in the Illinois law appears to be a hindrance to unambiguous communication from prescribers. In addition, because of the positive formulary approach adopted by Illinois, the potential for DPS behavior was limited to only 20.8 per cent of the prescriptions audited in the study and ultimately, DPS occurred in 12.6 per cent of this sample. It also is reported that DPS was more likely to occur in urban community pharmacies and that consumers saved more money when DPS occurred in this environment, but prices for prescriptions dispensed as written were also higher in this environment. Finally, it was found that prescription prices were affected by the type of pharmacy patronized, but were not affected by the urban or rural location of pharmacy.