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HF 6257

Getting Ready for Flexible Sigmoidoscopy

Read this entire document at least 1 week before your test. For a printable version of your bowel prep instructions and checklist click on download & print. This handout will tell you how to prepare for and what to expect after your flexible sigmoidoscopy. This test may be cancelled if you do not follow these instructions.

Flexible Sigmoidoscopy

A flexible sigmoidoscopy is a test to look at the lower part of your large bowel. This test can be used to find the cause of rectal bleeding or abdominal pain.

1 Week Before Test

Arrange Transportation

Due to the sedation medicines, you must have a responsible adult drive you home. It is recommended that you are observed for at least 6 hours after discharge.

Health Changes

Please tell us about any major health changes, illnesses, or recent hospital stays you have had since you scheduled your test. If at any time you have symptoms of illness (cough, stuffy nose, sore throat, fever, body aches, chills), please call the procedure center to reschedule your test. You should not have this test while ill.

Blood Thinners and Diabetes Medicines

You must call the doctor who prescribes this medicine to see if you need to stop or adjust your medicine before your test. That doctor will tell you how to safely do this.

The UW Digestive Health Center suggests talking to your doctor using the table below. That doctor should give you the final advice on stopping these medicines.

Ask your doctor about your bleeding risk with this test. If your doctor feels your bleeding risk is low, they will likely have you follow the schedule below to stop your blood thinning medicines. If your doctor feels your bleeding risk is high, they may have you follow a different timeline.

The list below has common blood thinning medicines. It does not include all blood thinning medicines.

DHC Med List

If your doctor tells you not to stop your medicine, please call the Digestive Health Center at 608-890-5010, as this may affect your procedure.

Iron, Multivitamins with Iron and Fish Oil

Stop taking these 5 days before your test. (You do not need to contact your doctor first).

3 Days Before Test

Pick up Bowel Prep

You will need to buy the bowel prep supplies before the procedure from a local drugstore. You do not need a prescription.

  • MiraLax (or store brand version) – 4.1-ounce bottle

  • Gatorade/PowerAde – buy two 32-ounce bottles. Do not buy red- or purple-colored liquids. (If you are diabetic, buy Pedialyte instead).

In some cases, the doctor may also want you to do an enema as a part of your bowel prep. Do not buy this unless your doctor tells you to. Some patients will have the enema here right before the procedure.

1 Day Before Test


You can eat a normal meal for lunch. Stop eating all solid foods by noon. After that, start a clear liquid diet.

Begin clear liquid diet. Be sure to drink at least 8 glasses of clear “see-through” liquids. Clear liquids include:

  • Water, clear sports drinks like Gatorade®

  • Broth

  • Black coffee, tea, soda

  • Apple juice

  • Jell-O®

  • No creamers, milks or other dairy products

  • No red or purple liquids or Jell-O

  • No solid food

  • No liquids with ‘pulp’


Take your daily medicines except those you were told to stop. Take at least one hour before or one hour after drinking your prep.

Mix the Prep

  • In the early afternoon, mix the MiraLax® with both bottles of chilled Gatorade. It will be 64 ounces total. If you are diabetic, use Pedialyte.

  • After you mix the prep, we suggest you put it in the fridge. Take it out of the fridge at least 2 hours before you start drinking it, so you won’t feel too cold.

Bowel Prep

  • Start drinking the prep at 6 pm.

  • Drink one 8-ounce glass of the total mixture every 15 minutes until gone.

  • Stay near a bathroom. You will have loose, then liquid stools. This is normal.

  • Drinking the prep through a straw may help improve the taste.

  • Between glasses, you can chew gum or suck on slices of lime or lemon or hard candies (avoid red or purple candy, as these can stain your colon).

  • After you mix the prep, we suggest you put it in the fridge. Take it out of the fridge at least 2 hours before you start drinking it, so you won’t feel too cold.

  • If you get chilled, try putting a blanket in the dryer to warm it up before using.

  • If your stool is still not clear, drink one 8-ounce glass of water every 15 minutes until your stool is clear.

Keep drinking clear liquids so you do not get dehydrated.

Test Day


  • No food

  • Stay on only clear liquids (no red or purple)

  • Stop drinking everything, even water, 4 hours before you arrive.

As you finish the prep, your stools should be watery clear or yellow, with no solids (flecks of stool are OK). If you are still passing solid or brown stools, call us at (608) 890-5010.


If you need to take medicine during the 4 hours before your arrival, drink no more than 1/2 cup of water (4 ounces). Follow your provider’s directions for your diabetes or blood thinning medicines.

What to Bring

  • CPAP or BiPAP and any inhalers that you use

  • Eyeglass or contact lens case, denture cup

  • Ostomy supplies

  • Wear comfortable clothing

  • Phone number for your driver

Do not bring:

  • Jewelry

  • Money

  • Other valuables

Before the Test

  • When you arrive, you can choose if your driver waits in the waiting room or in your private room where they will hear private health information.

  • The doctor will talk with you, answer questions, and ask you to sign a consent form.

  • A nurse will review your health history, take your vital signs and attach a heart monitor.

  • A nurse will place an IV and give you medicines to help you relax and keep you comfortable.

  • Your visit will take about 2-3 hours.

After the Test

  • Your doctor will review the results and give you a report. We strongly suggest that you have your driver in the room with you to hear the results.

  • You may feel tired when you leave.

  • Spend the day resting at home. You cannot drive or return to work. You can return to your normal routine the next day.

  • It may take up to a week for your bowel habits to return to your normal.

  • If you stopped blood thinning medicine before your test, ask when it can be restarted.


If you have biopsies taken or polyps removed, you can expect to get lab results 1-2 weeks later. Your results will be sent to your MyChart account. If you don’t have a MyChart account, someone will call you with results or results will be mailed to you

Tip: To learn more about colon polyps visit: :

When to Call

  • If you are still passing solid stools or your bowels have not started to empty by the morning of your test.

  • You have severe cramps.

  • You feel dizzy or lightheaded.

  • You have constant pain, rectal bleeding and/or a fever.

Who to Call

Patient Resources

(They can help figure out if your insurance will cover transportation.)

Digestive Health Center

(608) 890-5010

UW Hospital GI Procedure Clinic

(608) 263-8094

Meriter/Unity Point

(608) 417-6389