Hi, I have been applying fluorouracil topical crème 5% to the lesion on my arm, as ordered. It has been 10 weeks, and the medicine is finally working.However, for the past 2 weeks I have diarrhea, and I believe it is caused by this cream. since the diarrhea stopped, when I discontinued the medicine. ;after starting it again, several days later, the diarrhea returned.