IBS is one of the most common disorders of digestive system producing a spectrum of symptoms such as persistent and recurring abdominal pain associated with the passing of motion, change of bowel habit (diarrhea, constipation, or alternate diarrhea and constipation), etc. without any apparent cause. The word syndrome means a group of symptoms. IBS is a syndrome because it can cause several symptoms in addition to those mentioned, like cramping, bloating, gas, frequent urge to pass stools, the sensation of incomplete evacuation etc.