The aim of an enema is to empty the bowels, to allow for a diagnostic examination of the gastrointestinal tract, or to administer medication for ulcerative colitis (UC).

UC is a type of chronic inflammatory bowel disease that causes inflammation in the bowel, including the rectum and the colon.

This article looks at what an enema for UC is and why a person would use one. It also looks at who can and cannot use these enemas, side effects, alternative enemas, and alternative UC treatments.

An X-ray of a person's colon after receiving a barium enemaShare on Pinterest
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An enema is a procedure that involves inserting gas or liquid into the rectum, the lower part of the large intestine.

A 2021 study showed that during the procedure, people may have some discomfort but not usually experience pain. If a person does experience pain, they should inform a doctor, as they may stop the enema and consider alternative options.

Read more about enemas and pain.

Doctors may suggest different types of enemas for UC, both to diagnose and treat the condition. The types include the following:

A radiographer or radiologist will pass a white liquid called barium through the person’s rectum into their bowel. They will then assess the level of inflammation in the bowel on an X-ray.

A person will usually receive a barium enema in a hospital radiology department or stand-alone imaging center.

Doctors do not recommend barium enemas as often as they used to and will more often suggest alternative tests, such as CT scans or colonoscopies. However, in some cases, a barium enema may be a useful way to find the cause of a bowel problem.


Before a barium enema, a person will have to ensure their bowel is empty. The doctor may ask the person to:

  • Eat light meals in the days leading up to the barium enema and eat low fiber foods, such as lean meat, clear soup, and white bread.
  • Take a laxative medication the day before the enema.
  • Drink plenty of fluids to remain hydrated and replace lost fluids.


The following steps are what a person can expect to happen during the enema:

  • A person will lie on their side on an X-ray table.
  • A radiologist will insert a soft tube into the rectum. They will pass barium into the tube, which will carry the barium into the bowel. They may ask the person to move around to help the barium spread.
  • The radiologist will pump air into the person’s bowel to help expand it and move the barium around the space.
  • The person may have several X-rays of the bowel in different positions to determine the extent of inflammation.

Read more about a barium swallow examination.

Potential side effects of a barium enema and the laxative medication include:

Mesalamine is an anti-inflammatory medication that is prescription only. A person can use it to treat UC, as it reduces swelling and can help with healing.


A person can usually continue with their standard diet before and during the enemas at home.

The medication works most effectively on an empty bowel, so a person should try to have a bowel movement before performing the enema.

Mesalamine stops the body from producing a substance that leads to inflammation. A person may receive mesalamine as an anal suppository or an enema.

Dosage and frequency

The dosage prescribed will depend on the:

  • type and brand of mesalamine
  • severity of the condition
  • length of time the person will take the medication
  • person’s weight and age

A person usually needs to perform an enema once daily at night. They may feel an improvement within days or weeks once they start the enemas, but they should not discontinue the enemas until their doctor advises them to do so.


  • Lie on the left side with the right leg bent, or kneel on the floor while resting the chest and one arm on the bed.
  • Apply lubricant to the applicator if necessary and insert it gently into the rectum, pointing toward the navel.
  • Tilt the bottle so the nozzle is aimed at the back and squeeze it slowly to release the medication.
  • Withdraw the applicator and remain in the same position for 30 minutes to allow the medication to spread. It is best to perform the enema at bedtime so the medication remains in the system for 8 hours while sleeping.
  • Safely dispose of the bottle and do not reuse it.

A person can consult the Food and Drug Administration (FDA) Safe Disposal of Medicines website for more information on safe disposal.

Potential side effects may include:

Who it may not be suitable for

A pregnant or breastfeeding person may be able to safely continue using mesalamine but should consult their doctor first.

Some medications may interact with mesalamine. These include aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen.

Budesonide rectal foam enemas are corticosteroids, which help alleviate inflammation in the bowel. A professional can perform an enema on an individual or the person can perform an enema themselves at home.


These enemas work most efficiently when the bowel is empty, so a person should use them at the same time each day when the bowel has been emptied.

Budesonide rectal foam does not cure UC, but it can help relieve bowel inflammation.

Dosage and frequency

Each budesonide applicator holds a 2-milligram dose of foam. A person should use one dose per day.

The length of use depends on various factors, such as the severity of the condition and the type of enema prescribed. A person may need to use them for 4–8 weeks.


  • Turn the can upside down and keep a finger on the dome at the bottom of the can.
  • Lie on one side or stand with one leg raised onto a chair. Gently insert the applicator into the rectum.
  • Push down on the dome, which fills the applicator with a dose of foam, and slowly release the dome.
  • Wait up to 15 seconds before removing the applicator, and then remove it quickly.
  • Dispose of the applicator safely.

Potential effects of budesonide rectal foam enemas may include:

  • nausea
  • gas
  • diarrhea
  • pain in the rectum

Serious but rare potential side effects include:

Who it may not be suitable for

People who are pregnant, trying to get pregnant, or are breastfeeding should discuss the use and safety of this medication with their doctor before using it.

Budesonide may interact with some other medications. These include:

Alternative types of enema include:

  • Steroids: A doctor may suggest a rectal hydrocortisone enema, which activates natural substances in the skin to help reduce itching, inflammation, and redness.
  • Cannabidiol (CBD): CBD is found in cannabis plants. A CBD enema may have the potential to reduce inflammation caused by UC, but more research is necessary.
  • Coconut oil: Research has found that coconut oil used in an enema may improve symptoms of colitis, although a person should discuss performing an enema of this type with their doctor first.
  • Apple cider vinegar: An enema made from a mixture of apple cider vinegar and warm water may help heal the digestive system. However, more research is necessary to determine whether this is true.

Mesalamine is also available in oral forms, such as tablets or granules. However, these may not be as effective as rectal forms for conditions that affect the lower bowel. A person should explore the options with their doctor to determine the best treatment for their symptoms.

Budesonide is also available in tablet, granule, and capsule form for UC.

A doctor may suggest certain types of enemas to diagnose and treat UC.

For diagnosis, a doctor may order a barium enema. This involves inserting barium fluid into the rectum and running X-rays to detect inflammation.

For UC treatment, a doctor may prescribe mesalamine enemas or budesonide enemas. A person can self-administer treatment enemas and will need to perform them daily for as long as their doctor recommends.

Both types of treatment enemas have potential side effects, although these are rarely serious. If a person is not able to perform enemas, mesalamine and budesonide are available in oral forms.