Prescription trends for stimulants, selective serotonin reuptake inhibitors (SSRI), and combination therapies for ADHD, comorbid and emotional disorders were evaluated by a retrospective population-based analysis of North Carolina Medicaid prescription claim files for the years 1992-1998. In the 7 year study period, prescription prevalence in school-aged children 6 to 14 years increased from 4.4% to 9.5% for stimulants, and from 0.2% to 1.5% for SSRIs. In preschool children, stimulant prescription prevalence increased from 0.6% in 1992 to 1.3% in 1998, and SSRI prevalence from <0.01% to 0.1%. Preschool children (aged 1-5 years) accounted for only 7.1% of all stimulant prescriptions and 2.2% of SSRI prescription claims for children aged 1-19 years. Combination therapy also increased in prevalence. In 1998, stimulant usage was highest in white male children (18.3%), compared to 3.4% in black female children. The respective prevalences for SSRIs were 2.8% in white males and 0.6% in black females. Increases were found in number of prescriptions filled, number of patients treated, and in percentage of children prescribed these medications annually. Stimulant usage of almost 10% in 1998 was greater than the reported ADHD prevalence. 
COMMENT. Annual prescription prevalence of stimulants, SSRIs, and combination therapies in North Carolina school-aged children increased significantly from 1992 through 1998, reaching almost 10% for stimulants and 1.5% for SSRIs. Stimulant usage in white children is twice that in black children, and males are medicated atleast twice as often as females. Whereas the higher prevalence of stimulant prescriptions in males may be explained by sex differences in susceptibility to ADHD, the race differences in treatment prevalence are not readily apparent. A greater aversion to stimulant usage among parents of black compared to white children is one possible factor.