Stool that is pale or grey may be caused by insufficient bile output due to conditions such as cholecystitis, gallstones, giardia parasitic infection, hepatitis, chronic pancreatitis, or cirrhosis. Bile salts from the liver give stool its brownish color. If there is decreased bile output, stool is much lighter in color.
Other causes of pale stool is the use of antacids that contain aluminum hydroxide. Stool may also temporarily become pale after a barium enema test.
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