Objective: The objective of this is to determine whether FDY003 represents a complementary therapy for colon cancer when it is injected using a syringe. Materials and Methods: High‑performance liquid chromatography (HPLC) analysis was performed to determine the active ingredients of FDY003. The effect of FDY003 on the proliferation of Colo205 cells was investigated using the 3‑(4,5‑dimethyl‑2‑thiazolyl)‑2,5‑diphenyltetrazolium bromide (MTT) assay. The antioxidant effects of FDY003 on Colo205 cells were ascertained using oxidative markers such as lipid peroxidation and 2,2‑diphenyl‑1‑picrylhydrazyl (DPPH) assay. Markers of apoptosis in Colo205 cells after treatment with FDY003 were also measured. Based on the in vitro results, in vivo experiments were performed using Colo205 cell‑induced xenograft mouse cancer model treated with FDY003. Results: HPLC analysis revealed that FDY003 contained various active ingredients known to possess antioxidant activities. The viability of Colo205 cells was decreased by FDY003 in a concentration‑dependent manner. Cancer size and weight were significantly decreased in the group treated with FDY003, similar to those in the group treated with anticancer drug irinotecan. The expression of Bcl‑2‑associated X protein and caspase‑3 was increased in cancer tissues derived from the FDY003‑treated group. Serum levels of lipid peroxidation and DPPH were also significantly increased in the FDY003‑treated group. Conclusion: FDY003 represents a potential complementary therapy for cancer due to its antioxidative effects and anticancer activity.