What Is an Enema? (2024)

What is an enema?

An enema is an injection of fluid directly into your rectum that helps you poop. You may get an enema at your healthcare provider’s office. Most people buy enema kits they use at home. They’re available without a prescription at most pharmacies.

People have used enemas for centuries to flush out poop (stool) in their colon (large intestine).

When should you have an enema?

You may need an enema to:

Relieve constipation: Usually, an enema is a last-ditch effort to relieve constipation. You may need an enema if you can’t poop and lifestyle changes haven’t helped you have a bowel movement. Usually, increasing your water and fiber intake can get things moving. If not, stool softeners you take by mouth may help. If that’s a no-go, it may be time to go directly to the source by trying an enema.
Treat fecal impaction: Severe constipation can cause poop to get stuck inside your colon, so it’s impossible to pass on your own. An enema is an invasive treatment option, but it’s much less invasive than other options, like removing the stool with surgery.
Prepare for surgery: You may need an enema to flush out poop before surgery on your colon or rectum. Getting rid of the poop reduces your risk of infection during surgery.
Prepare for a colonoscopy: During a colonoscopy, a provider inserts a scope into your anus (butthole) and through your rectum to check for abnormal growths inside your colon. Part of your preparation instructions may involve doing an enema the day before so your provider can get a clear view of your colon.
Have an imaging procedure: During a barium enema, a provider inserts liquid that contains a chalky white powder called barium into your rectum. The barium solution makes problem areas easier to spot on an X-ray.
Receive medicine: A healthcare provider may insert medicine directly into your colon using an enema. For example, some medicines administered via enema reduce inflammation associated with gastrointestinal diseases, like ulcerative colitis.

Some people use enemas to rid their bodies of toxins or lose weight, but there’s no evidence that enemas help with this.

What are the types of enemas?

Enemas come in varieties based on solution type, the enema’s purpose and the solution amount.

Solution type

Sodium phosphate enemas are the most common and fastest-acting type. A sodium phosphate enema is a mix of water and salt (saline). These enemas pull water from your colon and into your stool, so it’s easier to pass.
Glycerin enemas also pull water into your colon to soften stools.
Bisacodyl enemas stimulate your colon to move, so it pushes the poop out.
Mineral oil enemas lubricate your colon so that poop can slide through easily.
Barium enemas are only used during a special X-ray procedure.
Tap water enemas soften poop so it can pass more easily.

Some people mix homemade solutions that consist of ingredients like soap, vinegar, milk or even coffee. Not all homemade ingredients have been tested for safety, though. They can potentially irritate or injure your colon. If you need an enema, it’s worth it to purchase one that’s safe.

Purpose of the enema

Cleansing enemas clean you out fast — within a matter of minutes. You insert the liquid, and then you poop. Most enemas are cleansing enemas.
Retention enemas require you to “hold it” or retain the fluid for a bit so the enema has time to work inside your colon. For example, holding a mineral oil enema gives it time to lubricate your colon so you can poop easier.

Amount of solution

Large-volume enemas (from 500 to 1,000 milliliters of fluid) push fluid higher into your colon, cleansing it completely.
Small-volume enemas (less than 500 milliliters of fluid) clean the lower part of your colon, which may be all you need.

Regardless of the enema type, you should follow the instructions — to the letter — to ensure you’re inserting the right amount of fluid. Otherwise, you may experience unpleasant side effects. Too much fluid can damage your colon.