The symptoms of IBS may vary between individuals. Common signs and symptoms include: Diarrhoea, constipation, or alternating periods of diarrhoea and constipation Abdominal pain and cramps Bloating, which is worse after a meal or better after going to the toilet and passing bowel movements Harder or looser stools than usual A bloated belly Mucus in the stool Learn more about the signs and symptoms of IBS .