Do you need to take gastrografin for a barium enema?

Depends: Most commonly, barium is administered into the rectum (along with air) for barium enema. If there is suspicion of bowel perforation, water soluble gastrografin is used instead. Gastrografin is hyperosmolar and can cause fluid shifts (fluid moves from the blood to the GI tract) and should be used with caution in hemodynamically unstable patients. Colon is then imaged with x-rays/fluoroscopy.