THE USE OF METHYLPHENIDATE IN MICHIGAN

Objective: To describe the epidemiologic findings associated with the use of methylphenidate hydrochloride among children aged 0 to 19 years in Michigan. Design: A population-based data set of all prescriptions filed with the Michigan Triplicate Prescription Program during Februa ry and March 1992 was analyzed, maintaining complete anonymity. Settin g: State of Michigan. Participants: All patients receiving a prescript ion for methylphenidate who are residents of Michigan, and all physici ans prescribing methylphenidate. Interventions: None. Main Outcome Mea sures: Descriptive data. Results: Eleven of 1000 Michigan residents be tween the ages of 0 and 19 years received a prescription for methylphe nidate during the study period. Eighty-four per cent were boys. Boys a ged 10 or 11 years received more prescriptions for methylphenidate tha n any other age group-43 per 1000. The number of children receiving pr escriptions for methylphenidate ranged from 2.5 to 28 per 1000. The ra nge for boys aged 10 or 11 years was from 9.6 to 117 per 1000. Primary care physicians wrote 84% of all prescriptions; pediatricians wrote 5 9% of the prescriptions for patients younger than 20 years old. Half o f the prescriptions written by pediatricians were written by 5% of the pediatricians in the state. Conclusions: Michigan has been among the states with the highest per capita consumption of methylphenidate for the past 10 years. The major use of methylphenidate is for treatment o f attention deficit hyperactivity disorder. The number of boys in Mich igan aged 10 or 11 years who were treated with methylphenidate was sim ilar to the national prevalence of the disorder, 3% to 5%. A tenfold v ariation was noted in the percentage of children medicated when the da ta were analyzed by county. Relatively few pediatricians account for t he largest proportion of prescriptions. Future studies are needed to l ink the use of methylphenidate with diagnostic and treatment considera tions in attention deficit hyperactivity disorder.