- Abdominal pain, cramping or discomfort
- Excess gas, bloating
- Diarrhea or constipation
- In women, symptoms may occur more during menstruation
- Weight loss
- Vomiting
- Abdominal pain which is not relieved by a bowel movement or passing gas
- Rectal bleeding
- Difficulty swallowing
- Some medications
- Diet / stress / foods that stimulate, irritate or increase inflammation in the gut or intestines
- Infections in the gut
- Changes in bacteria flora of the gut (less of the good bacteria which health people have)
- Hormonal changes