Since the results of the MOSAIC trial demonstrated an improved disease-free survival in stage III colorectal patients treated with oxaliplatin combined with 5-fluorouracil and folinic acid when they were compared with those treated with 5-fluorouracil and folinic acid alone, the addition of this organoplatin to 5-fluorouracil and folinic acid has become first-line adjuvant treatment for stage III colorectal cancer. Unfortunately, there is a small population of patients who develop grade III/IV hypersensitivity reactions to oxaliplatin which, until recently, have interfered with further treatment with oxaliplatin-containing regimens. Successful oxaliplatin desensitization protocols for patients having severe oxaliplatin hypersensitivity reactions have been reported. However, none of these protocols, have incorporated magnesium and calcium salts. Retrospective data has suggested that pretreating colorectal cancer patients with magnesium sulfate and calcium gluconate before the administration of oxaliplatin may reduce the incidence of neurotoxicities induced by this drug. Therefore, we modified a previously published oxaliplatin-desensitization protocol by incorporating intravenous calcium gluconate and magnesium sulfate, and report a patient with stage IIIc colorectal cancer and prior severe hypersensitivity reactions to oxaliplatin who underwent successful oxaliplatin desensitization using this protocol.