Familial combined hyperlipidemia (FCHL) is a common lipid disorder characterized by high levels of cholesterol, triglycerides, or both. The basic metabolic abnormality is overproduction of apolipoprotein B-100. High atherogenicity has been attributed to all forms of FCHL. We evaluated combined bezafibrate-lovastatin therapy in 10 patients (9 men and 1 woman) with FCHL and markedly high cholesterol and triglyceride levels who were at high risk of coronary artery disease and who had not responded to diet and bezafibrate treatment alone. Eight patients had coronary artery disease, 6 had hypertension, and 3 had noninsulin-dependent diabetes mellitus. Lovastatin 20 mg/day was added to the bezafibrate 600 mg/day regimen for 6 weeks; the lovastatin dosage was then doubled to 40 mg/day for an additional 6 weeks. The addition of 20 mg of lovastatin resulted in decreases of 15%, 20%, and 13% in total cholesterol, low-density lipoprotein (LDL) cholesterol, and triglyceride levels, respectively. Increasing the dose of lovastatin to 40 mg resulted in further moderate decreases of 4%, 3%, and 8% in total cholesterol, LDL cholesterol, and triglycerides, respectively, compared with the 20 mg/day dosage. Although previous reports have emphasized the potential side effects of combination treatment with lovastatin and fibric acid derivatives, our patients tolerated the regimen well, with no significant subjective complaints or laboratory abnormalities. The bezafibrate-lovastatin combination is a possible therapeutic option for severe, resistant FCHL, but close medical supervision is needed because of potential side effects.