Maintenance of the red blood cell volume is a fundamental aspect of ensuring oxygen supply to the tissue. Recombinant human erythropoietin (rHuEPO) was approved for marketing in Japan in 1990 for the treatment of anemia in patients on dialysis. Recombinant human erythropoietin caused a significant increase in hemoglobin (Hb) levels in patients on dialysis. However, not all have a good response to rHuEPO therapy; the causes of rHuEPO failure include iron deficiency, infection, uremia, and interaction of some drugs. Juzen-taiho-to (TJ-48), a mixture of extracts from 10 medicinal herbs, has been used traditionally to treat patients with anemia, anorexia, or fatigue. To clarify the effect of TJ-48 on erythropoietin-resistant anemia, we studied the effect of TJ-48 in patients on hemodialysis with erythropoietin-resistant anemia. We divided 42 end-stage renal disease patients on hemodialysis with erythropoietin-resistant anemia (Hb<10.0 g/dL with rHuEPO 9000 U/wk or 15 U/kg/wk treatment) into 2 groups as follows: a TJ-48-treated group (TJ-48 group, 7.5 g/d, n=22) and a TJ-48 nontreated (control group, n=20). At the beginning of this study, there was no significant difference between the groups in age, sex, serum creatinine, blood urea nitrogen, serum iron, and ferritin. After 12 weeks of treatment, the Hb level had significantly increased from 8.4 +/- 1.1 to 9.5 +/- 1.3 g/dL (P=0.0272) in the TJ-48 group. C-reactive protein (CRP) had significantly decreased from 1.4 +/- 1.7 to 0.6 +/- 0.8 mg/dL (P=0.0438). There was a significant negative correlation between Hb and CRP in the TJ-48 group (r(2)=0.121, P=0.0066). In contrast, in the control group, Hb and CRP showed no significant changes throughout this study. Nor was there a significant correlation between Hb and CRP in the control group. In conclusion, TJ-48 was effective in improving erythropoietin-resistant anemia in end-stage renal disease patients. This effect was, at least in part, due to the anti-inflammatory effect of TJ-48 in patients on hemodialysis.