The results of combined interferon alfacon-1 and ribavirin therapy of 94 patients with chronic hepatitis C were analyzed. Complete data, including sustained viral response (SVR), were obtained in 88 patients. 46.8% of them achieved SVR. The most important factor influencing SVR, was the presence of HCV RNA in serum at weeks 12 and 24 of therapy. SVR in these cases was achieved in 14.3% and 0%, respectively. Eight patients discontinued therapy due to adverse events. Most frequent were depressive reactions due to interferon (3 cases), and severe anemia due to ribavirin (2 cases). 37% of patients developed thyroiditis, significantly more frequent in women (27 versus 9).