(Biliary Calculus): Stone-like objects in either the gallbladder or bile ducts, composed mainly of cholesterol and occasionally mixed with calcium. Most gallstones do not cause problems until they become larger or they begin obstructing bile ducts, at which point gallbladder “attacks” begin to occur. Symptoms usually occur after a fatty meal and at night. The following are the most common ones: steady, severe pain in the middle-upper abdomen or below the ribs on the right; pain in the back between the shoulder blades; pain under the right shoulder; nausea; vomiting; fever; chills; jaundice; abdominal bloating; intolerance of fatty foods; belching or gas; indigestion.