Patterns of current psychotropic medication use among 5,181 children with autism spectrum disorders (ASD) enrolled in a Web-based registry were examined. Overall, 35% used at least one psychotropic medication, most commonly stimulants, neuroleptics, and/or antidepressants. Those who were uninsured or exclusively privately insured were less likely to use >or=3 medications than were those insured by Medicaid. Psychiatrists and neurologists prescribed the majority of psychotropic medications. In multivariate analysis, older age, presence of intellectual disability or psychiatric comorbidity, and residing in a poorer county or in the South or Midwest regions of the United States increased the odds of psychotropic medication use. Factors external to clinical presentation likely affect odds of psychotropic medication use among children with ASD.