Reduction of Ritualistic Behavior in a Patient with Autism Spectrum Disorder treated with Antibiotics: A Case Report

Author(s): Kelly Barnhill, Dane Mosher, Joy Mong, Betty Tong, Rebeca Shearer, and Laura Hewitson

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder with wide-ranging symptoms, including deficits in social communication and social interaction, and restricted, repetitive patterns of behavior, interests or activities. Recent research suggests that antibiotics may have therapeutic effects on patients presenting with ritualistic and/or repetitive behaviors. In this study, we present a case report of a 34 month old boy with ASD with repetitive and ritualistic behaviors. The child’s repetitive and ritualistic behaviors were significantly reduced after taking the antibiotics amoxicillin, cefazolin, and bactrim for several infections across a six- month period. Short-term improvements were observed during multiple concurrent and short- term post-therapy evaluations. Shortly after antibiotic discontinuation, behavioral deterioration was reported. We conclude that in this case study, a child with ASD experienced improvements in ritualistic behaviors during antibiotic therapy. Evidence of improvements in symptomatic behavior warrants further research.