Just as autism coexists with mental retardation, autistic spectrum disorders may coexist with treatable psychiatric and neurological disorders (Tuchman, 2000). Treatment of such diagnosed disorders will not cure autism, but can, in some cases, enable a child to remain in less restrictive community placements and enhance the child’s ability to benefit from educational interventions (Cohen and Volkmar, 1997). Medications have been shown in some instances to enhance and to be enhanced by systematic, individualized behavioral intervention programs (Durand, 1982; Symons and Thompson, 1997).
More than 100 articles have been published on the use of psychoactive medications for autistic spectrum disorders. A more limited number of published reports include double-blind, placebo-controlled studies with young children with autism. Double-blind studies of haloperidol (Cohen et al., 1980; Campbell et al., 1982; Anderson et al., 1984, 1989), naltrexone (Campbell et al., 1990; Bouvard et al., 1995; Kolmen et al., 1997; Willemsen-Swinkels et al., 1995, 1996), clonidine (Fankhauser et al., 1992; Jaselskis et al., 1992), and fenfluramine (Stern et al., 1990) included young children with autistic spectrum disorders, some as young as 2 years of age. In addition, newer medications, including selective serotonin uptake inhibitors, atypical neuroleptics, other antidepressants, and stimulant medications such as methylphenidate, have been studied, although most not yet in double-blind studies. A double-blind, placebo-controlled study of Risperidone™ was completed in adults (McDougle et al., 2000), and a study in children is presently under way in the National Institute of Mental Health Research Units for Pediatric Psychopharmacology (NIMH RUPPs).
The key findings from the published studies include:
Haloperidol was effective in reducing aggression and agitation and had mixed results for improving learning with long-term users, but it carries significant risk of involuntary muscular movements (dyskinesias).
Naltrexone-treated groups showed less irritability and hyperactivity than placebo groups on some measures, particularly global ratings, did not differ from placebo groups on others, and showed increases in particular problem behaviors in some instances.
Clonidine-treated subjects showed improvements in hyperarousal but reported increased drowsiness, decreased activity, they showed increasing tolerance when used to treat attention deficit disorders.
Risperidone shows promise in treating aggression and agitation with less concern about the development of dyskinesias than for the older neuroleptics.
Open trials of serotonin selective uptake inhibitors have shown promise in treating stereotypic or perseverative behavior, possibly because of effects on anxiety.