We evaluated total ROS in parasites that were treated with 4a and VC, alone and in combination using the probe H2DCFDA by fluorimetry. Figure shows a significant increase in total ROS after 24 h treatment with 4a + VC combination compared with the compounds alone and untreated group. This increase in total ROS production was of 115.0%, 134.0%, and 89.0% for epimastigotes, trypomastigotes and amastigotes, respectively, compared with the control group.