Irritable bowel syndrome or IBS is a group of symptoms that affect your digestive system. It is a type of functional gastrointestinal (GI) disorder. These types of conditions are categorized as disorders of the gut-brain connection. IBS can change how our gut muscles relax and contract, resulting in pain, diarrhea and/or constipation. These are the most common types of IBS recognized in the medical community IBS with constipation - hard & lumpy stool IBS with diarrhea - loose