Surgical bowel prep: Patient instructions

Following the proper steps before your bowel surgery will help ensure that your operation goes smoothly.

How to prep for bowel surgery

You play an important part in preparing for your surgery. Let’s review what you will need to do.

Take your prescribed oral antibiotic

On the day before your surgery, you may have been prescribed an oral antibiotic—either neomycin, erythromycin, or both, depending upon your circumstances.
If prescribed, you will need to take one gram of neomycin and/or 500 milligrams of erythromycin at these specific times: 1 p.m., 2 p.m., and 11 p.m.

Drink only clear liquids

On the day before surgery, you should drink only clear liquids. Besides water, clear liquids may include:

  • Juices that do not contain pulp
  • Sports drinks like Gatorade
  • Black coffee or tea without cream or milk
  • Popsicles
  • Kool-Aid or other soft drinks
  • Carbonated beverages such as soda or pop
  • Clear broth
  • Hard candies, such as lemon drops

Do not eat or drink the following before bowel surgery

  • Clear liquids that have red dye in them.
  • Jell-O or other brands of gelatin.

Clean out your bowel before surgery

Cleaning out your bowel—which is also called the colon or large intestine—before your surgery is another important step. To do this, you will need to drink a special liquid, called a colon lavage solution, the day before your operation.

At the appointment before your surgery, your doctor will e-scribe a prescription directly to your pharmacy. This prescription should be picked up from your pharmacy. It is a powder that you will mix with water at home to make the colon lavage solution.

Mix your liquid solution

It’s very important that you follow the mixing instructions carefully. You may add a small amount of lemon juice to the liquid to help make it taste better. You will need to stop drinking clear liquids about one to two hours before you start taking the colon-lavage solution.

When should you start drinking the liquid solution?

You should start drinking the liquid between 10 a.m. and 1 p.m. the day before your surgery. Do not start any later than 1 p.m.

How often should you drink the solution?

Drink one full cup of the colon lavage solution every 10 minutes. The best way is to drink it quickly rather than sipping a little at a time. It may help to suck on a hard candy, like a lemon drop, between cups.

How soon will bowel movements begin?

Bowel movements usually begin within 30 to 60 minute after your first cup of the liquid.You may have mild stomach cramps or a feeling or fullness or the chills.

Is it okay to skip a cup?

If you get an upset stomach or throw up, you may skip a cup. But after 10 minutes, start drinking the liquid again as scheduled. If you missed any cups of the liquid, please add those to the end of the schedule.

What to do if you experience discomfort while preparing for bowel surgery

If you experience very bad stomach cramps, upset stomach, or vomiting, call University of Iowa Hospitals & Clinics at 1-319-356-1616. If it is during business hours ask to speak to a nurse in the Center for Digestive Diseases. If it is after hours or on the weekends, ask to speak to the Surgery Resident for the Center for Digestive Diseases.

Why is it important to clean your bowels before surgery?

It is important that you drink all of the colon lavage solution according to the schedule so that your bowel is completely cleaned and free of stool. Otherwise, it might be necessary to reschedule your surgery.

When you are all done drinking the colon lavage solution, you may continue to drink the clear liquids as identified earlier.

Expect further instructions right before your bowel surgery

You should expect either an appointment with or a phone call from the Anesthesia Department to discuss pre-surgical instructions and when to completely stop drinking all liquids.

You can also expect a phone call from a nurse or staff member from the hospital’s Operating Room or from the Ambulatory Surgery Center to tell you the time to check in and to re-instruct you on when to completely stop drinking all liquids.

When it comes to surgery, planning ahead is always important. Please don’t hesitate to ask your doctor or nurse any questions you may have or if you would more information.

Working together, we can best ensure a safe and successful surgery—and put you on the path to a speedy recovery.

Last reviewed: 
July 2016

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