 [ Symptoms ] i have a mole on my legs is it a cancerous mole [ Disease ] the exact cause of irritable bowel syndrome ibs is not known but stress and anxiety are believed to be factors it is important to note ibs is a long term disorder it is not something that comes and goes  usually a person who has symptoms of ibs has them regularly for many years on the other hand stress and anxiety can cause temporary upsets of the digestive tract too this is not ibs per se because the episodes go away stress and anxiety can cause stomach upset nausea diarrhea among other things it is also important to note colonoscopy and endoscopy tests are not used to diagnose ibs these tests may be given to rule out more serious bowel problems like crohn is disease so the fact your colonoscopy and endoscopy results were fine does not mean you do not have ibs you should talk to your primary care provider to find out what your diagnosis is    if you have a diagnosis at all wishing you well