A 43-year-old Hispanic man with uncontrolled diabetes mellitus and end-stage renal disease who was on dialysis presented to the emergency department after a fall. He denied loss of consciousness or prodrome. There was no history of hypoxia or substance abuse. Computed tomography (Figure 1) and magnetic resonance imaging (Figure 2) of the brain showed bilateral basal ganglia abnormalities. Magnetic resonance angiographic results were normal. A few days after his fall, he developed acute extrapyramidal symptoms. These hyperkinetic movements were not responsive to haloperidol. His symptoms persisted and he was referred to our movement disorders clinic. On examination he had severe generalized chorea. There was no family history of psychiatric or neurological disease, including Huntington disease. Laboratory findings revealed elevated levels of blood urea nitrogen, creatinine, and glucose. Other laboratory test results including ceruloplasmin level, copper level, heavymetal screen, antinuclear antibodies, hepatitis panel, peripheral blood smear, and human immunodeficiency virus were normal. The patient continued dialysis 3 times per week. Haloperidol therapy was discontinued and the patient began receiving pimozide, with significant improvement in his movements after 1 week.