Can ibs mimic appendicities ?

No: Acute appendicitis usually starts with periumbilical pain and moves to the right lower part of the abdomen. This is usually associated with nausea and sometimes vomiting with lack of appetite and temperature elevation. Patient normally don't want to move and don't have diarrhea. This is not a chronic condition.

Different: IBS (irritable Bowel Syndrome) is characterised by a pattern of abdominal pain / bloating with bouts of constipation or diarrhoea that has been present for many months. Appendicitis is serious and presents intially as pain around the belly button, increasing in intensity over a couple of days, typically becoming a severe pain in the right lower part of your abdomen. See a Dr to make a diagnosis