We treated hyperlipidemia in patients with nephrotic syndrome (NS) using pravastatin for more than one year. There were 7 cases consisting of 3 with minimal change nephrotic syndrome (MCNS), 1 with focal glomerulosclerosis (FGS), 1 with proliferative glomerulonephritis (PGN), 2 with membranous glomerulonephritis (MGN) and 1 of unknown origin. Three cases consisted of frequent relapsers, and 4 were steroid-resistant. Six randomly selected age- and sex-matched nephrotic patients were used as controls. The daily excretion of proteinuria was not decreased after pravastatin treatment, but, the serum albumin rose from 3.1 +/- 1.1 to 3.4 +/- 1.0 mg/dl. The serum total cholesterol level was significantly reduced from 401 +/- 174 mg/dl to 331 +/- 103 mg/dl in spite of an absence of marked change in the control group. However, there were no significant changes in the triglyceride and lipoprotein levels. The atherogenic index was 7.1 +/- 3.7 before and 2.8 +/- 1.7 after pravastatin treatment, respectively. Improvement of renal function defined by delta decrement of renal function per year (0.08 +/- 0.06 vs. 0.12 +/- 0.26) was observed after the discontinuation of pravastatin administration in 3 out of 4 intractable cases. We conclude that pravastatin has a potent effect in reducing the serum level of total cholesterol, but not triglyceride in NS. Furthermore, pravastatin can induce renal dysfunction especially in patients with intractable nephrotic syndrome.