D-Lactate-associated encephalopathy is a rare clinical syndrome characterized by dizziness, ataxia, confusion, headaches, memory loss, lethargy, and aggressiveness which may progress to frank but reversible coma. It occurs in patients with profound dysfunction of the short-bowel syndrome and is believed to result from massive carbohydrate malabsorption with resultant over-production of D-lactate and other organic anions by the colonic flora. Extremely elevated serum levels of D-lactate (but not L-lactate) confirm the diagnosis, but currently D-lactate is not clearly established as the putative neurotoxin. We describe a patient who repeatedly developed D-lactate encephalopathy after surgical removal of nearly the entire jejunum and ileum. Markedly elevated D-lactate serum levels were documented during an encephalopathic episode. Potential pathophysiologic mechanisms and the treatment rationale are discussed.