This invention relates to a method of treating drug side effects in cancer treatment. More particularly, the present invention relates to preventing, reducing, alleviating, or reversing diarrhea caused by the administration of the isothiazole 3-(4-Bromo-2,6-difluoro-benzyloxy)-5-[3-(4-pyrrolidin-1-yl-butyl)-ureido]-isothiazole-4-carboxylic acid amide in the treatment of cancer comprising the step of administering to a patient in need of such treatment, prior to, simultaneously, or sequentially, a therapeutically effective amount of 3-(4-Bromo-2,6-difluoro-benzyloxy)-5-[3-(4-pyrrolidin-1-yl-butyl)-ureido]-isothiazole-4-carboxylic acid amide or a pharmaceutically acceptable salt thereof, and a therapeutically effective amount of an anti-diarrheal agent, a bulking agent, or an anti-estrogen. The combinations of the present invention may optionally include an anti-hypertensive agent.