How to prepare for Lower GI Series?

To prepare for a lower GI series, patients must empty all solids from the GI tract during a “bowel prep,” which is usually done at home. The doctor provides written bowel prep instructions. Generally, patients follow a clear liquid diet for 1 to 3 days before the procedure.

Acceptable liquids include

• fat-free bouillon or broth
• strained fruit juice
• water
• plain coffee
• plain tea
• sports drinks, such as Gatorade
• gelatin

A laxative or enema is usually used the evening before a lower GI series. A laxative is medicine that loosens stool and increases bowel movements. Laxatives are usually swallowed as a pill or as a powder dissolved in water. An enema involves flushing a liquid solution into the anus using a special squirt bottle. Enemas are sometimes repeated the morning of the test.

Sometimes, especially when only the rectum or end of the colon is being evaluated, emptying all solids from the entire GI tract beforehand is not necessary. Instead, the patient undergoes one or more enemas the day of the procedure to remove solids from just the large intestine.

Before starting the bowel prep, patients should tell their doctor about all health issues and medications. Women who may be pregnant should discuss getting an alternate test, such as colonoscopy, or taking precautions to minimize radiation exposure to their unborn child.