We present a case of a 29-year-old male who was brought into the hospital due to unresponsiveness and found to have heroin inhalational leukoencephalopathy (HLE). HLE is one component of a broad spectrum of opioid encephalopathies that is associated with heroin inhalation and other opioids. There is considerable overlap of HLE with other toxic and hypoxic-ischemic encephalopathies; however, the specific territories of brain involvement help distinguish it from other cerebral insults. The goal of this study is to help elucidate the findings of HLE and compare these findings to other toxic and hypoxic-ischemic encephalopathies.