This study is a prospective, triple-blind, randomized clinical trial to compare the effects of topical silymarin1% with placebo in prevention of hand foot syndrome induced by capecitabine in patients with gastrointestinal cancers (esophagus, gastric, colorectal). In this study 40 patients with gastrointestinal tract cancer diagnosis referring to oncology ward of Imam Reza hospital, Mashhad, Iran who decided to be treated with chemotherapy regimen included capecitabine have been selected based on random number table to receive topical silymarin gel1% or placebo gel which produced by Goldaroo company. The placebo/silymarin formulations are defined as A or B by producer and the oncologist, pharmacy student and clinical pharmacist who analyzed the data are not aware of formulation type. They should use half knuckle of cream on the soles of the feet and a knuckle of cream on the palm of the hands twice a day. At the beginning of the study, we record patients’ characteristics like age, gender, weight, height, body surface area, past medical and drug history, type of chemotherapy regimen and its duration. In both groups, patients are followed regarding hand foot syndrome occurrence every three weeks for nine weeks based on WHO grading scale. The patients with grade 3 or 4 (based on WHO grading scale) of HFS who need to decrease the dosage of capecitabine will be excluded from this trial.