Liquid fluoxetine versus placebo for repetitive behaviors in childhood autism

Introduction and Overview Autism is a pervasive developmental disorder distinguished by marked deficits in socialization, communication, and repetitive behaviors and/or restricted interests (American Psychiatric Association, 1994). Associated symptoms may include attentional difficulties, impulsivity, aggression, self-injurious behavior, and abnormalities of mood and affect. When broadly defined, approximately 60/10 000 individuals meet criteria for autism, rendering it a considerable concern for families, educators, and health care professionals (Fombonne, 1988). Due to its unknown etiology and heterogeneous presentation in the population, there is no standard pharmacological treatment for autism. However, the core and associated symptoms of autism overlap with other disorders. Therefore, it is possible to develop targeted pharmacological treatments for autism by utilizing medications that effectively treat similar problem behaviors in other disorders (Hollander et al., 2003a). Repetitive behaviors and restricted interests represent a hallmark symptom domain in autism. However, there appears to be a phenotypic overlap between the repetitive behavior domain in autism and other disorders, such as obsessive-compulsive disorder (OCD). For example, both groups of patients share a rigid adherence to routine and restricted interests. Patients with autism more commonly endorse low-order motoric repetitive behaviors such as tapping, rubbing, ordering, and hoarding whereas patients with OCD more often report repetitive behaviors such as cleaning, checking, and counting. However, these high-order repetitive behaviors also are endorsed in the autistic population (McDougle et al., 1995). We have reported familial linkage of repetitive behaviors in which autistic children with high levels of repetitive behaviors have higher rates of parents with OCD in comparison to children with low repetitive behaviors (Hollander et al., 2003b).