Transverse myelitis (TM) is a rare inflammatory myelopathy presenting as bilateral neurologic deficit localized to the spinal cord. A critical management step in the emergency department (ED) is evaluating for and treating acute reversible causes such as mass lesion or reversible ischemia when present. Described in this case report is TM presenting after a respiratory arrest in suspected opioid overdose. Magnetic resonance imaging (MRI), ideally with contrast, and lumbar puncture are essential diagnostic studies to confirm inflammation. Finally, further diagnostic efforts are aimed at evaluation and treatment for other concurrent illnesses.TopicsTransverse myelitis, transverse myelopathy, hypoxia, opioid overdose, hypoxic spinal cord injury.