Section 1A 48-year-old woman with an alcohol use disorder presented with a subacute onset of altered mental status. Two months prior to presentation, the patient recreationally used morphine, oxycodone, and heroin over the span of 1 week. At the end of this 7-day period, she experienced an episode of lethargy for approximately 24 hours and continued to be difficult to arouse during the following 2 days; however, she did not seek medical attention. She returned to her baseline functional status and remained asymptomatic until 3 weeks later, when she fell and hit her head, initially resulting in a headache. One day later, she began exhibiting bizarre behavior that gradually increased in severity over the following month. She began by sleeping with a recently deceased relative's ashes and emotional labiality and progressed to brushing her teeth with a comb, showering while dressed, undressing and then going outside, and not recognizing family members. Her husband brought her to the hospital for further evaluation.Her neurologic examination demonstrated that she was only oriented to self and had poor comprehension due to an inability to follow commands or respond appropriately to questions. Moreover, she demonstrated apraxia, aphasia, and selective mutism. Additional neurologic findings included patellar hyperreflexia, a palmomental reflex, and a wide-based gait. The remainder of the examination was limited by patient participation.