We have retrospectively been collecting data on adverse reactions to FOLFIRI chemotherapy in our hospital from September 2005 to August 2006, by electronic medical records. The retrospective study was of 67 patients who received FOLFIRI for advanced colorectal cancer. Survey results showed high incidences of vomiting(58.2%), anorexia(91.4%), constipation (47.8%), diarrhea (61.2%) and alopecia(71.6%). The first cycle using FOLFIRI therapy, vomiting (20.9%), anorexia(53.7%), constipation ( 14.9%), and diarrhea (23.9%)were observed. We sought to minimize inter-individual differences in pharmaceutical care and drug consultation by clinical pharmacists and to ensure the accurate understanding of patients. We are sure that this kind of activity will help us to provide better pharmaceutical care for patients.