The protective effects of carwin capsules (CAR) against toxicity induced by cyclophosphamide (CYC) in mice were investigated using the micronucleus assay for anticlastogenic activity in mouse bone marrow cells. The experimental animals were pre-treated orally with the drug suspension (carwin capsule suspension) for seven consecutive days (drug alone in group III and in combination with standard drug in group IV). The standard drug (cyclophosphamide, 50 mg/kg bw) was dissolved in saline and injected intraperitoneally. The results demonstrate that carwin was found to be significant (P<0.05) as compared to cyclophosphamide treated as the no. of MNPCEs in carwin treated was decreased effectively. And also carwin was able to significantly (P<0.01) protect the action caused by cyclophosphamide as well was also found to be very effective antigenotoxic (P<0.01) as compared to cyclophosphamide in scoring of PCE: NCE ratio. All the groups were compared with cyclophosphamide (-ve control). So, it was concluded that the used polyherbal formulation (carwin) was found to be very effective drug in cancer therapy as it has very less genotoxic effect as compared to cyclophosphamide and also has a protective effect with cyclophosphamide.
 Keywords: Carwin capsules, Cyclophosphamide, Micronucleus assay, Antigenotoxic, Polyherbal formulation.