We conducted a single, blinded cross-over placebo versus lovastatin study on 10 continuous ambulatory peritoneal dialysis (CAPD) patients with dyslipoproteinemia who failed to respond to diet control. They were given 8 weeks of lovastatin (20-40 mg) and placebo, respectively. After 8 weeks of lovastatin treatment, total cholesterol was significantly reduced by 28.6% (6.68 +/- 0.26 mmol/L, mean +/- SEM, to 4.77 +/- 0.12, p < 0.01); low-density lipoprotein cholesterol by 40.5% (4.57 +/- 0.27 mmol/L to 2.72 +/- 0.09, p < 0.01); apolipoprotein B by 32.4% (115.9 +/- 6.99 mg/dL to 78.3 +/- 2.9 mg/dL, p < 0.01); and triglyceride by 17.8% (1.92 +/- 0.38 mmol/L to 1.58 +/- 0.32, p < 0.05). Simultaneously high-density lipoprotein cholesterol increased by 7.6% from 1.24 +/- 0.13 mmol/L to 1.34 +/- 0.16, p < 0.05. There were no significant changes in other lipid profiles between placebo and drug treatment. No significant adverse effects were observed with lovastatin treatment. Lovastatin appears to be effective in treating dyslipoproteinemia in CAPD patients.