Click to expand Tap to zoom Irritable Bowel Syndrome | IBS by GIANTmicrobes Save $-18.99 $18.99 | / 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Add to cart Irritable bowel syndrome (IBS) is a very common, chronic gastrointestinal condition. IBS affects an estimated 15% of the global population, and in the USA alone over 50 million people have IBS symptoms.