A phase 1 trial was performed in 12 healthy volunteers to primarily investigate safety of Derris scandensas well as to preliminary assess its effects on immune system. The volunteers received 400 mg/day of D. scandens hydroalcoholic extract (200 mg b.i.d.) for 2 months. No major side effects were reported from any of the subjects throughout the study. It was found that any significant changes in hematological and biochemical parameters were within normal limits. A significant rise in the frequencies of subjects with increasing amounts of IL-2, IL-4 and IL-6 after administration was shown. Our results suggested that the hydroalcoholic extract of D. scandens at the dose of 400 mg/day given to normal volunteers for 2 months was safe and could induce the secretion of cytokines that might help in modulating immune responses.