Lower GI Series (Barium Enema)
A lower GI series uses x-rays to look at your large intestine which includes your colon and rectum. A lower GI series is sometimes called a barium enema because the large intestine is filled with a chalky liquid called barium.
When is a lower GI series done?
A lower GI series can be used to help find the cause of:
- Diarrhea that does not go away.
- Bleeding from the rectum.
- Abdominal (belly) pain.
- Changes in bowel habits.
- Unexplained weight loss.
A lower GI series is done by a radiology technologist or a radiologist (a doctor who specializes in x-ray imaging) at a hospital or outpatient center.
How do I prepare for a lower GI series?
To prepare for a lower GI series, you must get rid of all solids in your intestines. You will be given specific instructions to follow, as these can differ from one center to another.
Your instructions may include a clear liquid diet for 1 to 3 days before the exam. A clear liquid diet means that you can have liquids (broth, ginger ale, tea, Gatorade) and some foods (jello) that are “clear” or you can see through. Do not eat or drink anything with red, blue, or purple coloring.
You may also need to take a laxative or enema the night before the test. Instructions will be given on which to use.
If only your rectum or the end of your colon is being tested, you may not need to empty all solids from your entire GI tract. Instead, you will be given one or more enemas on the day of the procedure to remove solids from the large intestine.
Tell your healthcare provider about any health issues before having this test. This includes allergies to medications and/or foods and all medications you are taking. If you have kidney disease, you may need to follow special preparation instructions. You should let your care team know if you are or might be pregnant. Special precautions can be taken to lessen radiation exposure to the baby.
How is this test done?
For this test, you will lie on an x-ray table. A lubricated tube is inserted into your anus. Barium liquid is put through the tube into your large intestine. Leakage of barium liquid is stopped by an inflated balloon on the end of the tube. You may feel some discomfort and will likely feel the urge to have a bowel movement.
X-ray pictures and sometimes video is taken while you hold still in different positions. You may be asked to hold your breath at some points during the test. If a technologist is doing the lower GI series, a radiologist (a doctor who specializes in medical imaging) will look at the images after the test is done.
When the imaging is done, the balloon on the tube is deflated. Most of the barium liquid drains back through the tube. You will then get rid of the remaining barium liquid into a bedpan or nearby toilet. An enema may be used to flush out the rest of the barium liquid. The entire procedure takes 30 to 60 minutes.
What can I expect after a lower GI series?
For an hour or so after the procedure, you may have bloating and cramping in the abdomen (belly). Repeated bowel movements and enemas during the bowel prep may cause your anus to be sore. For several days, barium liquid in the large intestine will cause your stools to be white or light-colored.
Unless otherwise directed, you may resume your normal diet.
Mild constipation from the barium liquid is the most common side effect. To avoid this, drink plenty of fluid after the exam.
How do I receive the results of my lower GI series?
You may receive some test results on the same day. The official results and report of the test are usually available in 7-10 days. Your healthcare provider will discuss these results with you.
When should I call my care team?
In rare cases, barium can block the intestines. This can be a serious, life-threatening condition. Symptoms of this are:
- Severe abdominal (belly) pain.
- Being unable to have a bowel movement within 2 days after the procedure.
- Being unable to pass gas.
- Bleeding from the rectum.
Barium can also cause an allergic reaction. Signs of an allergic reaction include hives, itching, difficulty breathing, agitation, or confusion.
Call your care team if you have any of these rare side effects. If you are unable to contact your care team, call 911 or visit an emergency room.
U.S. Department of Health and Human Services. (2016, June). Lower GI series. National Institute of Diabetes and Digestive and Kidney Diseases. Retrieved September 15, 2022, from https://www.niddk.nih.gov/health-information/diagnostic-tests/lower-gi-series
Radiological Society of North America (RSNA) and American College of Radiology (ACR). (2021, July 20). X-ray (radiography) - lower GI tract. Radiologyinfo.org. Retrieved September 13, 2022, from https://www.radiologyinfo.org/en/info/lowergi