A 9-year-old, male castrated Labrador Retriever, was transferred to the Small Animal Internal Medicine Service of the Cornell University Hospital for Animals by the Emergency and Critical Care Service for a 3-day history of vomiting and anorexia, a 1-day history of diarrhea, and a 2- month history of right hind limb lameness. The dog had been on carprofen for 3 weeks. A chemistry panel and urinalysis revealed evidence of hepatocellular injury, cholestasis, and an acquired Fanconi-like syndrome. Supportive therapy (intravenous fluids, antibiotics, hepatoprotectants, and antiemetics) was initiated. An active Ieptospiral infection was rukd out by serologic testing. Cytological assessment of an ultrasonographic-guided liver aspirate revealed evidence of copper accumulation and inflammation. Histological evaluation of laparoscopic liver biopsies confirmed copper-associated hepatitis. Treatment consisted of chelation therapy, a copper-restricted diet, hepatoprotectants, appetite stimulants, and pyridoxine. All biochemical abnormalities eventually normalized 6 weeks after admission.