A previously healthy 2-year-old boy presented to the emergency department with a decreased level of consciousness. A physical examination was unremarkable except for miosis and atypical limb movements. The patient underwent an extensive workup, including the search for metabolic, infectious, neurologic, and toxicologic etiologies. An abdominal ultrasound was performed because the child continued to remain neurologically impaired with no cause identified on other investigations. The ultrasound revealed a persistent uncomplicated ileoileal intussusception. The patient was taken to the operating room for surgical reduction. The child recovered fully postoperatively. This case illustrates the rare presentation of intussusception encephalopathy, which can be a diagnostic dilemma, especially when none of the symptoms of intussusception are present. Endogenous opioid poisoning is hypothesized to be the cause of the miosis and may hint at the diagnosis and aid in early management.
