Am J Gastroenterol 116 (1): 17 - 44, 2021. doi: 10.14309 / ajg.0000000000001036 Key Points IBS is recurrent abdominal discomfort or pain accompanied by ≥ 2 of the following: pain is related to defecation, pain is associated with a change in frequency of stool (diarrhea or constipation), or pain is associated with a change in consistency of stool.