This handout teaches you to get ready for your colonoscopy with cystic fibrosis (CF). People with CF can have thick, sticky mucus lining their colon (large intestine). This mucus requires extra steps to properly clean out the colon to prepare for a colonoscopy. The goal of the colonoscopy is to find and remove any polyps in the colon. Polyps are growths that can become cancerous. A clean colon is needed to see these polyps.
2 Day Prep
Review Getting Ready for Your Colonoscopy (2-Day Prep using PEG Solution) (HFFY # 8386) at least two weeks before your visit.
Review the Prep Checklist on the last page. Make sure to review the timing of when to start and finish the prep solution based on your visit. Discuss any questions with your care team.
Scheduling
You will be asked a series of questions on the phone before scheduling. These questions include:
“Do you see a pulmonologist?”
“Do you frequently deal with constipation?”
Answer YES to the questions above even if you take a laxative or stool softener. CF raises the chance of constipation. This will help ensure you are correctly scheduled, make your endoscopist aware of your lung condition, and have the correct bowel prep ordered.
Health Status
We may suggest using a higher level of sedation if:
Your lung function is less than 50%
You had a lung transplant
You are being evaluated to receive a transplant
Medicines
Continue your CF treatments while doing prep, such as your nebulizer and airway clearance.
Diabetes
Check with your doctor who manages your diabetes for specific diet and medicine instructions.
Ask about the kinds of liquids and foods you should have to manage your blood sugar levels. You may need to adjust your insulin dose as part of your preparation.
CFTR Modulators
It’s okay to take these medicines the day of your test. Take at least 4 hours before you arrive. Drink water only, no fat needed. These medicines include:
Trikafta
Alyftrek
Kalydeco
Orkambi
Symdeko
Importance of Prep
Your doctor must see your colon wall entirely. If it is dirty, your doctor may not be able to see important things like polyps or cancer. As result, you may need to repeat the test.
Think about it like this: A dirty colon is like driving in a snowstorm, while a clean colon is like driving on a sunny day.
As you finish the prep, your stools should be watery clear or yellow. Stools should not be solid. If you are still passing solid or brown stools, please call the clinic you are scheduled at.

When to Call
Call the number below where your test is scheduled if:
You are sick
You’re having problems with your prep
You are not having clear stools
If you are concerned that your prep has not been successful, you may be able to still complete it with some more help.
Who to Call
The digestive health nurses will be your best resource for your bowel prep questions. Do not call the CF clinic.
UW Health Digestive Health Center
750 University Row, Madison, WI 53705
(608) 890-5010
UW Hospital GI Procedure Clinic
600 Highland Ave, Madison, WI 53792
(608) 263-8094
Meriter Digestive Health Center
202 S Park St, Madison, WI 53715
(608) 417-6389
Patient Resources (if you need help finding a ride to and from your test)
(608) 821-4144