Psychopharmacology in Autism Spectrum Disorders

Henry W.M. Kwok


Curr Opin Psychiatry. 2003;16(5) 

In This Article

Serotonin Reuptake Inhibitors

Symptomatic improvement has been reported in both open-label and controlled studies using selective serotonin reuptake inhibitors for the treatment of children and adults with autistic disorder.[35,36,37] Preliminary evidence suggested that this group of medication may be of particular benefit in reducing repetitive behaviors, aggression and, perhaps, self-injurious behaviors. Most of the earlier studies were on fluoxetine, but more recent ones also included other selective serotonin reuptake inhibitors. In a Canadian study by Couturier and Nicolson,[38*] 17 patients aged 4-15 years (14 with autistic disorder, three with Asperger's syndrome) were treated with citalopram for 1-15 months using a dose ranging from 5 to 40 mg daily. Outcome was based on a consensus between clinician and parents, using the Clinical Global Impression scale as a guide. Ten (59%) children were judged to be much improved or very much improved with regard to some interfering behaviors but the core symptoms (social interaction and communication) did not show clinically significant improvement. Few adverse effects were reported. Another small study reported excellent responses to fluvoxamine in two out of five autistic children whose self-injurious behavior and aggression did not respond to haloperidol or carbamazepine.[39]

Further progress was made by DeLong et al.,[40] who examined some factors that may affect the response to fluoxetine. A total of 129 children (aged 2-5 years) with ASD were studied. The response to fluoxetine was found to correlate robustly with a positive family history of major affective disorder (especially bipolar disorder) and unusual intellectual achievement. It is suggested that ASD may share some genetic determinants with these conditions.

On the other hand, with the increase in the use of selective serotonin reuptake inhibitors in the paediatric population,[41] there is a need to understand their pharmacokinetics more extensively in this age group. Dosage guidelines extrapolated from adult studies cannot necessarily be presumed to be applicable to children. Strauss et al.[42*] used fluorine magnetic resonance spectroscopy to evaluate age effects on whole-brain concentrations of fluvoxamine and fluoxetine in 16 children (aged 6-15 years) with diagnoses of pervasive developmental disorders. Their findings showed that paediatric brain levels of these two medications are not significantly different from adult levels when corrected for the effects of dose per body mass. Hence, it may be reasonable to determine the dose ranges for fluvoxamine and fluoxetine for children with this disorder by scaling down the adult doses on the basis of body mass.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.