Hi, My niece has been having nausea, vomiting, diarrhea, and stomach pain for at least a week. We brought her to a doctor the other day, who thinks its from an ulcer, and gave her an anti-acid to use until the ulcer heals. However, I was curious about the diarrhea, because I hadn t known ulcers to cause diarrhea. I was wondering if it could be from a bacteria or if ulcers really can cause diarrhea? or if you have any other input? Thank you!