A 4-year-old girl with autism spectrum disorder and moderate intellectual disability presents with severe aggression toward peers and self-injurious behavior (head-banging). Behavioral and environmental modifications have been attempted without adequate response. Which medication is the drug of choice for managing these behavioral symptoms?

Explanation

## Pharmacological Management of Aggression and Self-Injurious Behavior in ASD **Key Point:** Aripiprazole and risperidone are the only FDA-approved antipsychotics for irritability and aggression in children with autism spectrum disorder. Aripiprazole is often preferred as first-line due to favorable metabolic profile and lower risk of weight gain compared to risperidone. **High-Yield:** In ASD, aggression and self-injurious behavior are among the most common indications for pharmacotherapy. Second-generation antipsychotics (SGAs) are evidence-based and FDA-approved for this indication. ### FDA-Approved Antipsychotics in ASD | Agent | FDA Approval | Indication | Key Advantage | Key Disadvantage | |-------|--------------|-----------|---------------|------------------| | Risperidone | Yes (age 5+) | Irritability, aggression, SIB | Rapid onset | Weight gain, metabolic effects | | Aripiprazole | Yes (age 6+) | Irritability, aggression, SIB | Lower metabolic risk | Akathisia, restlessness | | Olanzapine | No | Off-label use | — | Significant weight gain | | Quetiapine | No | Off-label use | — | Sedation, metabolic effects | **Clinical Pearl:** Aripiprazole is increasingly preferred in pediatric ASD because it has the lowest propensity for weight gain and metabolic syndrome among SGAs, critical in a population already at risk for obesity. ### Dosing of Aripiprazole in ASD - Starting dose: 1–2 mg/day - Titration: Increase by 1 mg every 5–7 days - Typical maintenance: 5–15 mg/day (weight-dependent) - Maximum: 15 mg/day in children < 50 kg ### Monitoring Requirements 1. **Baseline:** Weight, height, BMI, fasting glucose, lipid panel, prolactin, EPS assessment 2. **Ongoing:** Weight and BMI monthly for 3 months, then quarterly 3. **Metabolic:** Fasting glucose and lipids at baseline, 3 months, and annually 4. **Neurological:** Monitor for extrapyramidal side effects (EPS), tardive dyskinesia, akathisia **Warning:** Antipsychotics carry a black-box warning for increased mortality in elderly patients with dementia; this does not apply to children with ASD, but clinicians must still monitor for metabolic and neurological side effects. ### Why Aripiprazole Over Risperidone? - **Lower weight gain risk:** Aripiprazole is weight-neutral; risperidone causes significant weight gain in 40–50% of children - **Metabolic profile:** Aripiprazole has minimal effect on glucose and lipids; risperidone increases both - **Prolactin:** Aripiprazole does not elevate prolactin; risperidone causes hyperprolactinemia **Mnemonic:** **ARIA** = **A**ripiprazole **R**educes **I**ncreased **A**ppetite (relative to risperidone) [cite:American Academy of Child and Adolescent Psychiatry Practice Parameters for ASD, 2020]