BACKGROUND Elevation in total and low-density lipoprotein cholesterol levels and a decrease in high-density lipoprotein cholesterol plasma concentrations are common in heart transplant recipients. The pathogenesis of this hyperlipemia after heart transplantation is complex. Currently available antilipemic agents are difficult to use because their adverse effects are potentiated by immunosuppressor treatment. The present investigation was carried out to test the safety and efficacy of lovastatin and bezafibrate in 18 patients with hyperlipemia after heart transplantation. METHODS In this crossover study, after 3 months of dietary recommendations, the subjects were randomly assigned to an 8-week period of lovastatin treatment (10 mg/day) followed by an additional 8-week period of treatment with bezafibrate (400 mg/day) or vice versa. The two treatments were separated by an 8-week washout period. RESULTS Both drugs reduced total and low-density lipoprotein cholesterol and apoprotein B concentrations. High-density lipoprotein cholesterol was only increased with bezafibrate. The total cholesterol/high-density lipoprotein cholesterol and low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratios were decreased under both treatments, but these changes were greater with bezafibrate. Apo AI levels increased with lovastatin. Bezafibrate produced a rise in high-density lipoprotein cholesterol and reduced total and very low-density lipoprotein triglycerides and very low-density lipoprotein cholesterol. Both drugs decreased intermediate density lipoprotein cholesterol and triglyceride levels, but the effect of bezafibrate on intermediate-density lipoprotein triglycerides was significantly greater. The two drugs were well tolerated and liver enzymes, creatine kinase, and renal function remained stable.