Docetaxel is used to treat various types of carcinomas. Since docetaxel is insoluble in water (solubility, 0.002 mg/mL), to improve its solubility, it is administered with alcohol. The amount of alcohol required to improve the solubility of Onetaxotere® is twice as much as that required to improve the solubility of Taxotere®.In this study, we investigated the immediate breath alcohol level of and feeling of drunkenness experienced by patients after administration of chemotherapy with Onetaxotere®. The study was performed in 50 patients, from March 2012 to June 2012. In addition, 25 patients served as controls: these patients were administered chemotherapy with paclitaxel. Breath tests revealed no alcohol in any of the patients who were administered Onetaxotere®. Furthermore, none of these patients experienced a feeling of drunkenness. In contrast, breath tests performed in the control patients revealed alcohol in 15 cases, and 4 out of the 15 patients experienced a feeling of drunkenness.Breath tests revealed alcohol in 60.0% of the patients who were administered paclitaxel. The result is similar to those reported in other studies. No alcohol was detected in any of the patients who were administered Onetaxotere®. Moreover, these patients did not experience a feeling of drunkenness. These findings suggest that the patients who received Onetaxotere® were unaffected by the alcohol used to administer the drug.