A double-blind comparison of clomipramine, desipramine, and placebo in the treatment of autistic disorder.

OBJECTIVE

To determine whether clomipramine hydrochloride, a serotonin reuptake blocker with unique anti-obsessional properties, is differentially effective for obsessive-compulsive and stereotyped motor behaviors in autistic disorder compared with placebo and with the noradrenergic tricyclic antidepressant agent, desipramine hydrochloride.

DESIGN

Following a 2-week, single-blind placebo washout phase, 12 autistic subjects completed a 10-week, double-blind, crossover comparison of clomipramine and placebo, and 12 different subjects completed a similar comparison of clomipramine and desipramine.

SETTING

Outpatient clinic.

PATIENTS

A referral sample of 30 male and female autistic patients were enrolled, and 24 completed the study.

MEASURES

Key outcome measures were the Autism Relevant Subscale of the Children's Psychiatric Rating Scale, the Modified Comprehensive Psychopathological Rating Scale-Obsessive-Compulsive Disorder Subscale, and the Clinical Global Impressions Scale.

RESULTS

Clomipramine was superior to both placebo and desipramine on ratings of autistic symptoms (including stereotypies), anger, and compulsive, ritualized behaviors (P < .05), with no differences between desipramine and placebo. Clomipramine was equal to desipramine and both tricyclic agents were superior to placebo for amelioration of hyperactivity.

CONCLUSION

Biological links between compulsions and stereotyped, repetitive behaviors in autistic disorder should be explored.