We estimated the effect of atorvastatin and fluvastatin on plasma antioxidative activity used in coronary heart disease (CHD) primary prevention. Anti-oxidative activity of blood plasma was determined by Bartosz et al. method [Curr. Top. Biophys. (1998)22:11-13], based on reduction of preformed cation radical of 2,2,azinobis(3-ethylbenzothiazoline-6-sulphonic acid) by blood plasma. The study comprised 35 patients with CHD risk who were randomly divided into two groups. The atorvastatin group comprised 17 patients who were administered the drug orally in a daily dose of 10 mg and the fluvastatin group consisted of 18 patients on an oral dose of 40 mg once daily. The control group comprised 12 healthy subjects with no drug administration. Blood samples were collected from cubital vein before and after 6-week therapy. Significantly (P < 0.05) increased--in comparison with the initial values--antioxidative activity of blood plasma was found in atorvastatin and fluvastatin groups after 6-week therapy. Moreover, the increase in antioxidative plasma activity in atorvastatin group was significantly higher in comparison with the fluvastatin group. The results of our study have demonstrated that atorvastatin and fluvastatin have an additional mechanism independent of the effect on cholesterol concentration. Thus, we presume that administration of these statins in CHD risk patients may have a beneficial effect.