OBJECTIVES: I. Evaluate the efficacy of fluoxetine on social and language deficits, global severity and compulsive dimensions of children and adolescents with autism.

II. Assess the effectiveness of this treatment regimen on neurocognitive deficits in this patient population.

III. Compare the baseline compulsive severity and treatment outcome in these patients.

PROTOCOL OUTLINE: This is a randomized, double blind, placebo controlled, crossover study. All patients receive oral placebo daily during week 0.

Patients are randomized to receive either oral fluoxetine or oral placebo daily on weeks 1-8. Patients then crossover to receive treatment on the other arm during weeks 12-20.

PROTOCOL ENTRY CRITERIA:

--Disease Characteristics--

Meets diagnostic criteria for autism

--Prior/Concurrent Therapy--

Other:

• At least 3 months since prior electroconvulsive therapy
• At least 1 month since prior investigational drugs or treatment with any drug known to cause major organ toxicity
• At least 2 weeks since prior monoamine oxidase inhibitors
• At least 6 weeks since prior long acting phenothiazines
• At least 1 week since prior other psychotropic drugs
• No prior fluoxetine of 20 mg/day for 6 weeks
• At least 6 weeks since prior fluoxetine
• No concurrent use of terfenadine (Seldane) or astemizole (Hismanal)
• No concurrent electroconvulsive therapy or other psychotropic drugs (unless otherwise permitted)
• Prior participation in another serotonin reuptake inhibitor trial allowed

--Patient Characteristics--

Hematopoietic: No significant hematopoietic disease

Hepatic: No prior or concurrent liver disease

Renal: No prior or concurrent kidney disease

Cardiovascular:

• No significant cardiovascular disease
• No abnormal EKG

Neurological:

• No prior seizure disorder or high risk development of seizures
• No prior cerebrovascular disease
• No prior brain trauma

Other:

• Not pregnant or nursing
• Negative pregnancy test
• No unstable major medical illness or systemic disease
• No moderate or severe mental retardation and motor deficits (IQ less than 50)
• No family history of bipolar disorder
• No prior or concurrent other mental disorders (e.g., schizophrenia, schizoaffective, organic, or bipolar disorders)
• No significant autoaggressive behavior or serious suicidal risk
• No prior or concurrent gastrointestinal conditions
• No unstable endocrine disease (e.g., hypo or hyperthyroidism)
• No prior or concurrent malignancy
• Must be able to tolerate tapering of psychoactive medication
• No history of hypersensitivity or severe side effects to fluoxetine or other serotonin reuptake inhibitors
• No history of severe personality disorder or noncompliance