Table 18‐2. The Rome II criteria for IBS

IBS can be diagnosed based on at least 12 weeks (which need not be consecutive) in the preceding 12 months, of abdominal discomfort or pain that has two of three of these features:

1. Relieved with defecation; and/or

2. Onset associated with a change in frequency of stool; and/or

3. Onset associated with a change in form (appearance) of stool.

Symptoms that cumulatively support the diagnosis of IBS:

1. Abnormal stool frequency (>3 stools per day or <3 stools per week)

2. Abnormal stool form (lumpy/hard or loose/watery stool)

3. Abnormal stool passage (straining, urgency, or feeling of incomplete evacuation);

4. Passage of mucus

5. Bloating or feeling of abdominal distension

Red Flag symptoms that are not typical of IBS:

1. Pain that often awakens/interferes with sleep

2. Diarrhea that often awakens/interferes with sleep

3. Blood in stool (visible or occult)

4. Weight loss

5. Fever

6. Abnormal physical examination