In the United States, the use of unconventional medicine is widespread and increasing. Eisenberg and colleagues [1] estimated that in 1990, approximately $2 billion was spent on vitamin and commercial diet supplements. The authors suggested that physicians should elicit information on unconventional therapies and medicines when taking patients' medical history. Even when such a history is taken, however, physicians may not have information on the efficacy and safety of these "alternative" medications. Shark cartilage is one such medication that has been in the media spotlight and is available as a food supplement [2].

We evaluated a 57-year-old man who presented with a 3-week history of nausea, vomiting, diarrhea, and anorexia. He took no prescription medications but began taking shark cartilage dietary supplements 10 weeks before hospitalization. Because of a change in the odor of the supplements, he stopped taking the supplements a few days before his symptoms began. He smoked one pack of cigarettes per day but denied using alcohol or drugs. He had no history of blood transfusions. His physical examination showed a low-grade fever, jaundiced skin, scleral icterus, and mild tenderness of the right upper quadrant. The patient's liver had a smooth edge and was estimated to have a 12-cm diameter. Notable laboratory values were an aspartate aminotransferase level of 319 U/L (normal, 0 to 45 U/L), an alanine aminotransferase level of 404 U/L (normal, 3 to 36 U/L), an alkaline phosphatase level of 430 U/L (normal, 30 to 125 U/L), a total bilirubin level of 12.9 mg/dL, and a direct bilirubin level of 6.8 mg/dL.

The patient's evaluation included ultrasonography of the right upper quadrant and computed tomography of the abdomen, both of which yielded unremarkable results. Results of hepatitis serologic tests, as well as tests for antinuclear antibody, ferritin, and acetaminophen levels were also unrevealing. Endoscopic retrograde cholangiopancreatography showed no abnormalities. The patient was discharged with the presumed diagnosis of drug-induced hepatitis. A follow-up examination, done 6 weeks after discharge, showed normal liver function.

To date, no reports have linked shark cartilage supplements with hepatitis. Although this case cannot indisputably prove the association, it does make a case for greater scrutiny of dietary supplements. Because such supplements are not tightly regulated, we encourage physicians to report any possible adverse reactions.