Lack of Efficacy of Citalopram in Children With Autism Spectrum Disorders and High Levels of Repetitive Behavior: Citalopram Ineffective in Children With Autism

CONTEXT Selective serotonin reuptake inhibitors are widely prescribed for children with autism spectrum disorders. OBJECTIVES To determine the efficacy and safety of citalopram hydrobromide therapy for repetitive behavior in children with autism spectrum disorders. DESIGN National Institutes of Health–sponsored randomized controlled trial. SETTING Six academic centers, including Mount Sinai School of Medicine, North Shore–Long Island Jewish Health System, University of North Carolina at Chapel Hill, University of California at Los Angeles, Yale University, and Dartmouth Medical School. PARTICIPANTS One hundred forty-nine volunteers 5 to 17 years old (mean [SD] age, 9.4 [3.1] years) were randomized to receive citalopram (n = 73) or placebo (n = 76). Participants had autistic spectrum disorders, Asperger disorder, or pervasive developmental disorder, not otherwise specified; had illness severity ratings of at least moderate on the Clinical Global Impressions, Severity of Illness Scale; and scored at least moderate on compulsive behaviors measured with the Children's Yale-Brown Obsessive Compulsive Scales modified for pervasive developmental disorders. INTERVENTIONS Twelve weeks of citalopram hydrobromide (10 mg/5 mL) or placebo. The mean (SD) maximum dosage of citalopram hydrobromide was 16.5 (6.5) mg/d by mouth (maximum, 20 mg/d). MAIN OUTCOME MEASURES Positive response was defined by a score of much improved or very much improved on the Clinical Global Impressions, Improvement subscale. An important secondary outcome was the score on the Children's Yale-Brown Obsessive Compulsive Scales modified for pervasive developmental disorders. Adverse events were systematically elicited using the Safety Monitoring Uniform Report Form. RESULTS There was no significant difference in the rate of positive response on the Clinical Global Impressions, Improvement subscale between the citalopram-treated group (32.9%) and the placebo group (34.2%) (relative risk, 0.96; 95% confidence interval, 0.61-1.51; P > .99). There was no difference in score reduction on the Children's Yale-Brown Obsessive Compulsive Scales modified for pervasive developmental disorders from baseline (mean [SD], –2.0 [3.4] points for the citalopram-treated group and –1.9 [2.5] points for the placebo group; P = .81). Citalopram use was significantly more likely to be associated with adverse events, particularly increased energy level, impulsiveness, decreased concentration, hyperactivity, stereotypy, di