Gallstones are produced in the gallbladder—part of our digestive system—and are small deposits that most often form when substances in the bile harden. It is estimated that about 10 to 15 percent of adults have gallstones. The usual symptoms of a pain around the abdomen, back, or just under the right arm occur most often if a blockage is in the gallbladder’s duct that releases the bile—most often caused by a gallstone. The one positive part about having gallstones is that for most people, the removal of the gallbladder has little effect, as bile has other ways of getting to your small intestines.