Yulda-Hanso-Tang (YH-Tang) is a prescription for the Taeumin cerebral infarction (CI) patients according to Sasang constitution philosophy. Taeumin patients with CI were treated with YH-Tang during the acute stage. Clinical signs of CI disappeared markedly in about 2 weeks after oral administration of YH-Tang in all patients. The mean interleukin (IL)-2 serum levels were lower in the patients with CI than in the normal groups, whereas the mean IL-4, IL-6 and IgE levels were significantly higher in the patients. There were no significant differences in interferon-gamma (IFN-gamma) levels between the groups. Serum IFN-gamma and IL-2 levels derived from T helper (Th)1 cells elevated significantly in the patients with CI by YH-Tang administration. Significant reduced serum levels of IL-4 and IL-6 derived from Th2 cells and IgE were observed in the patients treated with YH-Tang. During the period of YH-Tang administration, there were no other adverse effects. The data indicate that YH-Tang has a good CI treatment effect, and that its action may be due to regulation of cytokine production.