We have been collecting data on the adverse reaction of FOLFOX 4 chemotherapy in our hospital from April 2005 to October retrospectively, by electronic clinical records. A retrospective study of 123 patients receiving FOLFOX 4 for advanced colorectal cancer was conducted. Survey results showed high incidences of hemotoxicity (52.8%), chronic sensory neuropathy (16.2%) and allergic reactions (15.4%). In the initial FOLFOX 4 therapy, appetite loss (60.1%), vomiting (19.5%) and acute sensory neuropathy (33.3%) were observed. We prepared a brochure in order to minimize inter-individual differences in pharmaceutical care and drug consultation by clinical pharmacists and to ensure the accurate understanding of patients. We feel sure that this kind of activity will help us to provide better pharmaceutical care for patients.