A patient is described with acute pancreatitis which was probably caused by furosemide. Administration of furosemide on two separate occasions was associated with increases in serum amylase concentrations and recurrence of abdominal pain. This case is of further interest because of the presence of hyperlipemia in the absence of an underlying lipid abnormality. Following recovery from pancreatitis, the lipoprotein pattern evolved from type V to type III, type IIA, and finally to normal.