Patterns of Psychotropic Medication Use in Children with Autism Spectrum Disorders

Background: Increasingly, children with Autism Spectrum Disorders (ASD) are being treated with psychotropic medications, many of which have not been studied in children. Research on medication use in this population is typically conducted through survey methods using cross-sectional data. A longitudinal approach provides the advantage of capturing sequences in medication trials as well as other patterns of medication use.

Objectives: This study prospectively examines medication use in children with ASD, aged 2 – 10 years.  This study has four objectives; to assess the proportion of children using psychotropic medications, to describe patterns of polypharmacy, to investigate usage by medication class, to examine age of initiation, and to describe the average length of medication trials by class.

Methods: This sample of 75 children with ASD participated in a multidisciplinary, longitudinal study on behavioral and neurobiological predictors of outcome in autism. Participants received diagnostic assessments at 3-4, 6 and 9 years of age. Every six months from age 3 through 11, parents participated in a telephone assessment of their child’s medication use.  Parents were asked to list medications their children took each month.   

Results: Preliminary results indicate 52% of children used at least one psychotropic medication between age 2 and age 10. At age two, 0% of children were using a psychotropic medication, 8% used medication at age three, 13% at age four, 24% at age five, 31% at age six, 36% at age seven, 40% at age eight, 31% at age nine, and 34% at age ten.  Of the children receiving psychotropic medication, 28% received two or more medications for at least three months, and 10% received three or more medications. The proportion of children on each medication class and average age of initiation by class include: stimulant (17%; 7.4 years), antidepressant (17%; 6.6 years), antipsychotic (9%; 6.7 years), other psychotropic (7%; 7.1 years), anticonvulsant (5%; 8.1 years), antiparkinsonian (1%; 6.3 years), and anxiolytic (0.7%; 6.5 years).  Average length of trial was 11 months for stimulants, 18 months for antidepressants, 12 months for antipsychotics, 19 months for other psychotropics, 15 months for anticonvulsants, 25 months for antiparkinsonians, and 12 for anxiolytics. Further analyses will also explore the sequence of medication use, specific medication use within each drug class, and child characteristics associated with medication use.

Conclusions: Psychotropic medications are frequently used in children with ASD. Over half of children with ASD in this sample were prescribed a psychotropic medication at some point between the ages of 3 and 10.  The percentage of children on psychotropic medication increased from age 2-6 and appeared relatively stable from 7-10 years. Stimulants were the most common class of psychotropic medication used, followed by antidepressants and antipsychotics. The current study provides information about the use and timing of medications in children with ASD. Findings suggest individual medications and medication combinations that should be studied further, and may inform future clinical trials.