(Medical Xpress) -- Restricted, repetitive behavior, such as compulsive arranging and rigid adherence to routines, is a defining symptom of autism spectrum disorders.
A 12-week study showed that the antidepressant fluoxetine produced a greater decrease in repetitive behaviors and more overall improvement than placebo in adults with autism spectrum disorders.
The study by Eric Hollander, M.D., of the Albert Einstein College of Medicine and Montefiore Medical Center and colleagues from Mt. Sinai School of Medicine represents the first largescale, double-blind, placebo-controlled trial of fluoxetine in adults that targeted changes in the core domain of repetitive behaviors as well as overall functioning. Overall improvement in autistic symptoms occurred in 35% of individuals receiving fluoxetine and none of those receiving placebo. Half of the individuals in the fluoxetine group experienced substantial improvement in their repetitive behaviors (versus 8% of those receiving placebo).
Previous trials of treatments for these disorders have mostly tested interventions for children. An earlier high-profile trial of another antidepressant, citalopram, did not reduce repetitive behaviors in children with autism spectrum disorders.
Although treatments for common characteristics have been studied, Dr. Hollander notes, Research on medications for the core features of autism spectrum disorders is still in the early stages, and successful treatments could greatly improve the daily lives of patients and their families.
The report will be published online on December 2, 2011, at AJP in Advance, the advance edition of The American Journal of Psychiatry, the official journal of the American Psychiatric Association.
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