This study aims to compare two FDA approved medications (aripiprazole and risperidone) for the treatment of behavioral dysregulation in children with autism spectrum disorders. This trial, done in the context of routine clinical care, will seek to evaluate whether aripiprazole or risperidone is associated with more weight gain in children.

Autism is a developmental disability with increasing prevalence in our society. Currently one out of fifty-nine children in the United States has this condition. Many children with autism experience behavioral dysregulation such as irritability and aggression.

Currently, there are two FDA approved atypical antipsychotic medications that treat irritability in children with autism. These are aripiprazole and risperidone. While it is thought that aripiprazole may cause less weight gain than risperidone, clinically this has not been proven.

Understanding the relative risk of ATAP-induced weight gain that results from risperidone versus aripiprazole in a real-world setting could help guide the choice of medical intervention and reduce the cardiometabolic risks, and, most critically, address the limitations of current studies, which have not been able to provide clear clinical insights given the difficulty with having a representative and robust number of patients enrolled.

To be enrolled in this study, participants must be younger than 18 years of age, on the autism spectrum, have behavioral dysregulation, be naive to treatment with atypical antipsychotics and be seen either in the Division of Developmental Medicine or Child and Adolescent Psychiatry at Vanderbilt University Medical Center.

For enrolled patients, the ordering provider will see an order set, randomized to either aripiprazole or risperidone. They will then choose the recommended antipsychotic that the patient has been randomized to, or override the prompt. If the provider overrides the prompt, they will be asked to provide a reason for not choosing the recommended option.

The outcome measure for this study will be weight gain at a 3 month follow-up visit.

Inclusion Criteria:

• age 17 years and younger
• diagnosed with autism
• have behavior problems
• seen in Vanderbilt clinic
• naïve to atypical antipsychotics

Exclusion Criteria:

• 18 years or older
• history of atypical antipsychotic use
• not diagnosed with autism