What Is a Barium Enema?

What to expect when undergoing this test

A barium enema, also known as lower gastrointestinal (GI) series, is a procedure in which a liquid containing barium sulfate is introduced into the rectum to obtain high-contrast X-ray images of the large intestine (colon).

On its own, an X-ray produces poor images of soft tissue. By coating the tissue with barium, a chalky crystalline compound, the radiologist is able to get a relatively clear silhouette of the colon. A barium enema uses a technique called fluoroscopy, which produces real-time video images, making it possible to see the colon and adjacent structures in motion.

what to expect during a barium enema
 Illustration by Cindy Chung, Verywell

Purpose of Test

A barium enema is an indirect form of visualization used to examine the anatomy of the colon and occasionally the terminal ileum (the junction between the small and large intestines).

It may be recommended by your healthcare provider if you have:

  • Chronic diarrhea
  • Chronic constipation
  • Rectal bleeding
  • Unexplained abdominal pain
  • Unexplained weight loss
  • Unexplained changes in bowel habits

Use in Diagnosis

A barium enema is useful in highlighting abnormalities, growths, or changes in the structure of the colon that can indicate the possibility of:

  • Bowel obstruction, such as caused by adhesions (scarring), volvulus (twisting), or intussusception (the telescoping of the intestine into itself)
  • Celiac disease, an immune reaction to gluten resulting in the flattening of the intestinal lining
  • Colon polyps, fleshy growths in the colon that have the potential to turn cancerous
  • Colorectal cancer, cancer of the colon and/or rectum
  • Diverticular disease (including diverticulosis and diverticulitis), in which abnormal pockets form in the intestine
  • Inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis

Test Limitations

All of that said, barium enema is almost never used today.

The test is not a reliable means of diagnosis of rectal disorders. Moreover, research suggests that it is more likely to miss small tumors when compared to a computed tomography (CT) scan (26.6% versus around 6.7% to 9.4%, respectively).

Because of this, these days, your healthcare provider is more likely to recommend direct visualization techniques, such as colonoscopy, or more sophisticated forms of imaging, such as a transrectal ultrasound or CT colonography.

Colonoscopy is far more reliable in identifying strictures (intestinal narrowing) or fistulas (the abnormal of seepage from fluids) than a barium study.

A barium enema may be used to diagnose gastrointestinal bleeding, but only if direct visualization methods are not possible. It has a limited role following complex surgery.

Risks and Contraindications

A barium enema is a relatively safe procedure during which you are exposed to relatively low levels of radiation.

Complications of a barium enema are rare but may include:

  • Arrhythmia (irregular heartbeat)
  • Barium impaction leading to bowel obstruction
  • Dilutional hyponatremia (water intoxication)
  • Drug allergy (occurring in only one of 750,000 cases)
  • Bowel perforation leading to acute peritonitis and shock

A barium enema is contraindicated during pregnancy and for people with acute gastrointestinal bleeding or active colitis. It should be used with caution in elderly or frail people and only if no other form of diagnosis is possible. If there is rectal inflammation or you had a recent rectal biopsy, the procedure should be delayed until the rectum is healed.

Before the Test

The preparations for a barium enema are quite extensive. The instructions need to be strictly followed to ensure minimal discomfort or optimal imaging.

Timing

When scheduling a barium enema, set aside at least two hours of your day. While the imaging itself can take anywhere from 15 to 20 minutes, the entire procedure from start to finish may take an hour or more. You may also need a short time to recover if you experience symptoms and are given an antispasmodic injection during the test.

Try to arrive at least 30 minutes in advance of your appointment so that you can sign in, relax, and not feel rushed.

Location

A barium enema is performed in a radiology unit at a hospital or a specialized testing facility. The room itself is equipped with a radiographic table, a fluoroscopic X-ray machine with one or two tubes, and a digital monitor enclosed within a protected viewing compartment.

The room will also have an enema stand with an enema tube. A bathroom will be close by.

What to Wear

You will need to undress for the procedure. Bring comfortable clothes that you don’t mind staining in case you have some rectal leakage on the way home. While the office will likely have lockers to store small belongings, it is best to leave any jewelry and valuables at home.

Bowel Preparation

In order to obtain accurate images of your colon, you will need to completely empty your bowel of any fecal matter. This requires a restricted diet, laxatives, and possibly an enema. This is referred to as bowel preparation.

Once the appointment is scheduled, you will be given written instructions outlining what you can eat and how to vacate your bowel. In addition, your healthcare provider will either give you a laxative dose to take home with you (in pill or liquid form) or provide you a prescription to fill at the pharmacy.

The bowel preparation instructions can vary, but more or less follow a similar sequence:

  • 24 hours before the test, you will restrict yourself to a clear liquid diet. This includes the avoidance of milk or cream.
  • At around midday, you will take a laxative at the time and dosage prescribed by your healthcare provider. You will need to stay home and close to a bathroom, as the laxative will trigger frequent and watery bowel movements.
  • For the rest of the day, you will need to drink plenty of fluids to keep hydrated. You may also want to apply some petroleum jelly to your anus after each bowel movement to avoid chafing.
  • At bedtime, you may need to take another dose of the same or a different laxative. Some labs recommend this two-part procedure; others don’t.
  • At midnight, you will need to stop drinking or eating altogether.

The morning of the test, some people use a ball douche or enema to ensure the bowel is completely clean, though this is not necessary if you have followed all of the preparation instructions. If you decide to douche, do not overly irrigate the bowel, as this can cause irritation.

If you have diabetes, speak with your healthcare provider about the appropriate foods to eat while on a clear diet and be sure to check your blood sugar frequently during the bowel preparation procedure.

Medications

When scheduling the barium study, be sure to advise your healthcare provider of any and all drugs or supplements you may be taking, whether they be prescription, over-the-counter, homeopathic, traditional, or recreational. Some of these may need to be stopped for a day or even several days in advance of the procedure.

These may include:

What to Bring

In addition to your ID and health insurance card, you may want to bring a sports drink or snack for after the test, since you will not have eaten for many hours. If you have diabetes, you should also bring your glucose monitor to check your blood sugar after the test.

While most labs provide you with a sanitary pad to protect your clothes from leakage, some people bring their own just in case. You may also want to bring an extra pair of socks for when you walk in the X-ray room.

If your child is undergoing the procedure, bring a favorite toy or comfort item as a distraction.

Cost and Health Insurance

The cost of a lower GI study can run anywhere from $200 to $2,000, depending on the provider and where you are having the test performed.

To this end, it is important to know the total costs in advance, including how much your health insurance will cover and what your co-pay and/or out-of-pocket expenses will be. With rare exception, the test requires insurance pre-authorization, which your healthcare provider’s office can submit on your behalf.

If you are denied coverage for any reason, ask your insurer for a written reason for the denial. You can then take the letter to your state insurance consumer protection office and ask for help. Your healthcare provider should also intervene and provide additional motivation as to why the test is essential.

If you are uninsured, you can speak with the lab to see if there are monthly payment options. Some independent labs even offer patient assistance programs with tiered pricing for low-income families.

Other Considerations

While a barium enema can often be unpleasant for adults, it may be downright distressing for a child. If your child is undergoing the procedure, explain in advance why the test is being done, and allow your child to ask as many questions as needed. It often helps to tell the child in advance that he or she may experience leakage and mess—and that adults do as well—so that the child isn't surprised or upset it if happens.

While you will likely be allowed to accompany your child into the imaging room, you will need to wear a protective apron and stand behind an anti-radiation barrier during the actual imaging.

During the Test

On the day of the test, after signing in and confirming your insurance information, you may be asked to sign a liability form stating that you are aware of the purpose and risks of the procedure. You will then be asked to change into a gown.

Pre-Test

In addition to removing all of your clothing, you will need to take off any jewelry, eyewear, or removable dental appliances. After changing into the gown, you will be met in the X-ray room by a radiologist and a radiology technician.

After you are positioned on the radiographic table, the technician will take several X-ray images to ensure your colon is clear. A digital rectal exam may also be performed.

A lubricated enema tube is eased into your rectum, and the tube is then connected to a pre-filled bag containing a mixture of barium sulfate and water. If your healthcare provider has requested a double-contrast (air-contrast) barium enema, carbon dioxide will also be pumped into your colon to provide a clearer image of the colonic structure.

The radiologist may give you a shot of Buscopan (butylscopolamine) to relax the walls of your colon and prevent spasms, particularly if you are undergoing a double-contrast procedure. The only exception would be for people with glaucoma or heart disease in whom the injected version of the drug is contraindicated.

At the end of the enema tube is a small balloon that can be inflated to keep liquid from seeping out of the rectum. As your colon fills with barium, you may feel the urge to have a bowel movement. This is normal. Try to relax and hold it in, taking long, deep, slow breaths. While the procedure may uncomfortable, it doesn’t usually cause any overt pain.

This part of the exam can take anywhere from 10 to15 minutes to complete.

Throughout the Test

Once enough barium has been introduced into your colon, imaging begins. This part of the procedure generally takes 15 to 20 minutes.

During the test, you may be asked to change positions to capture images from different angles. The radiologist may even press on your abdomen or pelvis to manipulate your colon into a better position for imaging.

Abdominal pressure and the urge to defecate are the most common complaints. To help alleviate the symptoms, take slow, steady, shallow breaths, inhaling through the nostrils and exhaling through the lips. If spasms occur, you can accelerate your breathing by taking shallow, panting breaths. Avoid "bearing down" or breathing with your diaphragm. Doing so can make things worse.

Generally speaking, if you remain calm and focus on your breathing, any discomfort you feel at the start of the test will usually subside within a few minutes.

If you have trouble keeping the fluid in, let the technician know. Don’t be embarrassed if you break wind or any fluid leaks out. This is a common occurrence and one that the radiology team is more than prepared for.

When completed, the majority of the barium solution is removed through the tube. You will then be directed to the bathroom to expel the rest. Most radiologists will recommend that you stay there for at least 10 to 15 minutes as it can take time to evacuate the bowels.

Post-Test

Once you have cleaned yourself and changed back into your clothes, the radiologist will want to see if you are experiencing any side effects, such as cramping or spasms. If you are, you may be asked to sit quietly until the symptoms pass. If you have diabetes, you will want to check your blood sugar and advise the medical staff if the reading is abnormal.

In most cases, you can drive yourself home after a barium enema. However, if you were given an antispasmodic injection, you may experience blurred vision for 30 to 60 minutes. If you're in doubt about your ability to drive, call a ride service or ask for a friend to pick you up.

After the Test

Before leaving, the lab may give you a gentle laxative to help clear the rest of the barium from your system. Take it as instructed. Thereafter, you can resume your regular diet and medication routine. Make every effort to drink plenty of water for the next 24 hours.

Managing Side Effects

Your stools may appear white for a day or two as your body gradually clears the barium from the bowel. Some people may also experience constipation, headache, upset stomach, and diarrhea. These symptoms tend to be mild and resolve within a couple of days.

To lessen these side effects, drink plenty of fluids and eat foods high in insoluble fiber. Saline cathartics (like Milk of Magnesia (magnesium hydroxide)) can gently treat stomach upset and constipation, while emollient cathartics (like mineral oil or glycerin suppositories) may ease bowel movements. Diarrhea can be treated with over-the-counter products like Imodium (loperamide). Use these products only as directed.

With that being said, if you do not have a bowel movement for more than two days or are unable to pass gas, call your healthcare provider. You may be experiencing barium impaction and need an enema.

Interpreting Results

A day or two after the test, your healthcare provider will review the results with you. The radiology report will detail both the expected and unexpected findings. It won’t necessarily diagnose your condition but rather outline what the findings suggest along with a list of possible causes.

In the end, a lower GI study is but one of several tools used to make a diagnosis. In addition to a review of your medical history and current symptoms, clinical judgment is needed to decide whether treatment can be started or further investigation is needed.

Follow-Up

Follow-up evaluations may be needed if the results are inconclusive or equivocal (ambiguous). While it can be disappointing, if you're insured, an ambiguous result may motivate your insurance company to approve a more expensive, specialized test.

If the lower GI study is able to pinpoint a cause, follow-ups will likely be needed to monitor your condition and/or assess your response to therapy.

A Word From Verywell

While a barium enema may be one of the more awkward imaging procedures, it does have its benefits. In the end, it is a nominally invasive technique with a low risk of complications. Because barium is not water-soluble, it cannot be absorbed in the blood (lowering the risk of allergic reactions). In some cases, a barium enema may provide just as much information as a more invasive colonoscopy and without the need for sedation. 

Moreover, modern X-ray systems are extremely dose-controlled to deliver the lowest level of exposure with minimal stray (scatter) radiation.

Generally speaking, the benefits of a barium enema far outweigh the possible consequences. If you are still uncomfortable with the procedure, speak with your healthcare provider about alternatives and why they may or may not be appropriate for you. 

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading

By Jennifer Whitlock, RN, MSN, FN
Jennifer Whitlock, RN, MSN, FNP-C, is a board-certified family nurse practitioner. She has experience in primary care and hospital medicine.