This case report describes a 2-year-old girl who presented to the emergency department with lethargy and possible seizure activity after opioid overdose. Initial CT scan showed symmetric low attenuation in the white matter and cerebellar hemispheres with effacement of the prepontine cistern, suggestive of opioid overdose. She was intubated for airway protection and respiratory support. Naloxone was administered but was ineffective. She was diagnosed with opioid-induced acute cerebellitis requiring ventriculostomy and suboccipital decompressive craniectomy for hydrocephalus and cerebellar edema. This case highlights the neurosurgeon's role in diagnosing and treating opioid overdose-induced