Outpatient prescription drug use by children enrolled in five drug benefit plans.

This study examined prescription drug use among ambulatory children younger than 18 years of age enrolled in five drug benefit plans. Data for this study were obtained from the pharmacy benefit manager who administers the drug benefit plans. During the study period of December 29, 1992, through December 28, 1993, 3144 children younger than 18 years of age (34.0% of the total plan enrollment) were enrolled in the five drug benefit plans. A total of 8547 prescription drugs were dispensed to the study population. The mean prescription price was $16.38, and the mean duration of therapy was 11.7 days. The mean prescription price was $1.56 more for boys than for girls. The most frequently dispensed drugs were antibiotics (42.0%), followed by cold preparations (15.9%). The annual prevalence rate of prescription drug use was 59.1 cases per 100 children. The study population-based annual frequency rate was 3.2 prescriptions per child, and the drug user-based annual frequency rate was 5.5 prescriptions per child. The annual expenditures were $51.85 per child and $90.39 per drug users, with the out-of-pocket expenditures being $19.09 and $33.04, respectively. The prevalence rate varied little by sex. However, both frequency and expenditure rates differed by sex and decreased with age. Higher levels of cost sharing per prescription were associated with higher prevalence, frequency, and expenditure rates. Larger cost-sharing differentials between generic and brand name drugs were associated with higher rates of generic drug use but were not always associated with lower expenditure rates.