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Digestive Enzyme Supplementation for Autism Spectrum Disorders: A Double-Blind Randomized Controlled Trial

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To examine the effects of a digestive enzyme supplement in improving expressive language, behaviour and other symptoms in children with Autism Spectrum Disorder. Randomized, double-blind placebo-controlled trial using crossover design over 6 months for 43 children, aged 3–8 years. Outcome measurement tools included monthly Global Behaviour Rating Scales, Additional Rating Scales of other symptoms by parents and therapists, and monthly completion of the Rescorla Language Development Survey. Compared with placebo, treatment with enzyme was not associated with clinically significant improvement in behaviour, food variety, gastrointestinal symptoms, sleep quality, engagement with therapist, or the Language Development Survey Vocabulary or Sentence Complexity Scores. A small statistically significant improvement on enzyme therapy was seen for the food variety scores. No clinically significant effect improvement of autism symptoms with enzyme use was shown with this trial, however, possible effects on improvement in food variety warrants further detailed investigation.

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The authors wish to extend their sincere gratitude to the children and families who so willingly gave their time to make this study possible. We would also like to thank Dr Devin Houston (PhD) and Houston Nutraceuticals for their willingness to allow this product to be examined in a controlled trial and assistance with providing product and placebo capsules for the study. We also wish to thank Margaret Shave (Clinical Trials Pharmacist, Princess Margaret Hospital, Perth, Western Australia) for her invaluable contribution to the study. The authors wish to acknowledge the support with respect to statistical analyses given by Gavin Pereira (University of Western Australia) and Elaine Pascoe (Child and Adolescent Health Service, Princess Margaret Hospital, Perth, Western Australia).

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Correspondence to Sujeeva A. Munasinghe.

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Munasinghe, S.A., Oliff, C., Finn, J. et al. Digestive Enzyme Supplementation for Autism Spectrum Disorders: A Double-Blind Randomized Controlled Trial. J Autism Dev Disord 40, 1131–1138 (2010).

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