A Randomized, Double-Blind, Placebo-Controlled
Trial of Porcine Versus Synthetic Secretin for Reducing Symptoms of Autism

Unis AS, Munson JA, Rogers SJ, Goldson E, Osterling J, Gabriels R, Abbott RD, Dawson GK
Department of Psychiatry and Behavioral Science, University of Washington, Seattle, WA 98195, USA.

Abstract: J Am Acad Child Adolesc Psychiatry 41:1315, 2002

 

Findings

Secretin is a hormone normally found in the body that regulates the function in the small intestine and pancreas. In recent years, many parents reported improvements in their autistic children after giving them secretin by infusions (injections) or transdermally (i.e., through the skin). It was thought that this hormone is somehow not being produced at normal levels in children with autism, possibly contributing to symptoms of the disorder.

Controlled studies examining the effects of secretin on symptoms of autism have been published. While some of these studies reported a positive effect on autistic behavior after infusion, final study outcomes indicated that secretin, even repeated doses, was not more effective than a placebo in improving the behavioral symptoms of autism.

Dr. Alan Unis and his colleagues at the University of Denver compared the effects of a single does of secretin, both of biologic (from pigs) and synthetic origin to placebo on a variety of autism symptoms. The reason two different types of secretin were used was because there has been some controversy about whether naturally occurring (biological) secretin is different in effect than synthetic secretin (produced in the laboratory).

A total of 85 children with autism (aged 3-12 years) without other medical conditions and not taking other medications were included in this study. Children were grouped into three groups matched by age and communication level and then randomly assigned to one of three treatment groups: biologic secretin, synthetic secretin, or placebo. Measures collected 1 week before and 4 weeks after infusion included autism symptoms, language skills, and problem behaviors, gathered from parents, teachers, and investigators, who were all "blind" to treatment (double-blind trial).

Direct observation measures did not change over time in chidren treated with secretin compared with placebo. Parents reported an overall reduction of symptom severity for all treatment groups, including the placebo group. One report from teachers described decreases in autism symptoms in the placebo as well as the synthetic secretin groups.

Conclusions

Despite the many reports that secretin is associated with improvement in symptoms of autism, this placebo-controlled, double-blind trial showed no such effect. The authors found no evidence that either biologic or synthetic secretin provided decrease of symptoms beyond placebo.

The authors conclude that there is no compelling evidence for the use of secretin for the treatment of autism, and that doctors are left with more traditional psychological or pharmacolotical treatments that aim to reduce symptoms.