Nuclear division index (NDI) was calculated to assess the effects of the decoction on the proliferative capacity of lymphocytes. NDI in lymphocytes treated with the decoction is same as that of control, suggesting no interference of the decoction in human lymphocyte proliferation. However, a significant delay in lymphocyte proliferation in the presence of bleomycin at a concentration of 40 μg/mL was observed. This was manifested by a change in relative numbers of M1 to M4 cells. However, restoration of NDI was observed in lymphocytes pretreated with the decoction prior to bleomycin induction. This reflects a successful overcome of cytotoxic effects caused by bleomycin, by modulating the lymphocyte proliferation.