Caring for patients with autism spectrum disorder

Hyperactivity and impulsivity

Hyperactivity and impulsivity are common among patients with ASD, with rates estimated from 41% to 78%.⁶¹ Hyperactivity and inattention are treated with a variety of medications. Research examining methylphenidate in ASD has demonstrated modest effects compared with placebo, though with frequent adverse effects, such as increased irritability and insomnia^62,63 Other smaller studies have confirmed these results.^64-66 One additional study found improvements not only in hyperactivity but also in joint attention and self-regulation of affective state following stimulant treatment.⁶⁷ There is limited data on the efficacy and tolerability of amphetamine for treating hyperactivity and impulsivity in ASD. Stimulant medications often are avoided as the first-line treatment for hyperactivity because of concerns about increased irritability. Alpha-2 adrenergic receptor agonists often are used before stimulants because of their relatively benign adverse effect profile. Clonidine, guanfacine, and guanfacine ER all have demonstrated effectiveness in double-blind, placebo-controls trials in patients with ASD.^68-70 In these trails, sedation was the most common adverse effect, although some studies have reported increased irritability with guanfacine.^70,71

The Table provides a summary of the target symptoms and their treatment options for patients with ASD.

Improved diagnosis, but few evidence-based treatments

The rise in ASD cases observed over the past 20 years can be explained in part by a broader diagnostic algorithm and increased awareness. We are better at identifying ASD; however, there are still considerable gaps in identifying ASD in high-functioning patients and adults. One percent of the population has ASD,^72,73 and this group is overrepresented in psychiatric clinic and hospital settings.⁷⁴ Therefore, we must be aware of and understand the diagnosis.

Medication treatments are often less effective and less tolerable in patients with ASD than in patients without neurodevelop­mental disability. There are differences in pharmacotherapy response and tolerability across development in ASD and limited evidence to guide prescribing in adults with ASD. SGAs appear to be effective across multiple symptom domains, but carry the risk of significant adverse effects. For anxiety and irritability, there is compelling evidence supporting the use of nonpharmacologic treatments.

Bottom Line

A subset of patients seen in psychiatry will have undiagnosed autism spectrum disorder (ASD). When evaluating worsening behaviors, first rule out organic causes. Second-generation antipsychotics have the most evidence for efficacy in ASD across multiple symptom domains. To sustain improvement in symptoms, it is vital to incorporate nonpharmacologic treatments.

Related Resources

• National Institute of Mental Health. Autism spectrum disorder. https://www.nimh.nih.gov/health/publications/autismspectrum-disorder/index.shtml.
• Centers for Disease Control and Prevention. Autism spectrum disorder (ASD). https://www.cdc.gov/ncbddd/ autism/index.html.

Drug Brand Names
Aripiprazole • Abilify
Clonidine • Catapres
Clozapine • Clozaril
Guanfacine • Tenex
Guanfacine Extended Release • Intuniv
Haloperidol • Haldol
Lithium • Eskalith, Lithobid
Lurasidone • Latuda
Methylphenidate • Ritalin
Olanzapine • Zyprexa
Paliperidone • Invega
Quetiapine • Seroquel
Risperidone • Risperdal
Ziprasidone • Geodon