High-Expenditure Pharmaceutical Use Among Children in Medicaid.

Background And Objectives: Medication use may be a target for quality improvement, cost containment, and research. We aimed to identify medication classes associated with the highest expenditures among pediatric Medicaid enrollees and to characterize the demographic, clinical, and health service use of children prescribed these medications.

Methods: Retrospective, cross-sectional study of 3 271 081 Medicaid-enrolled children. Outpatient medication spending among high-expenditure medication classes, defined as the 10 most expensive among 261 mutually exclusive medication classes, was determined by using transaction prices paid to pharmacies by Medicaid agencies and managed care plans among prescriptions filled and dispensed in 2013.

Results: Outpatient medications accounted for 16.6% of all Medicaid expenditures. The 10 most expensive medication classes accounted for 63.9% of all medication expenditures. Stimulants (amphetamine-type) accounted for both the highest proportion of expenditures (20.6%) and days of medication use (14.0%) among medication classes. Users of medications in the 10 highest-expenditure classes were more likely to have a chronic condition of any complexity (77.9% vs 41.6%), a mental health condition (35.7% vs 11.9%), or a complex chronic condition (9.8% vs 4.3%) than other Medicaid enrollees (all < .001). The 4 medications with the highest spending were all psychotropic medications. Polypharmacy was common across all high-expenditure classes.

Conclusions: Medicaid expenditure on pediatric medicines is concentrated among a relatively small number of medication classes most commonly used in children with chronic conditions. Interventions to improve medication safety and effectiveness and contain costs may benefit from better delineation of the appropriate prescription of these medications.