Preparing For A Colonoscopy When You Have Cystic Fibrosis

Colonoscopies are important in helping to screen and prevent colon cancer for everyone, but especially so for those with cystic fibrosis (CF). A colonoscopy allows the doctor to examine the inside of the large intestine, or the colon and rectum. They inspect to see if there are any polyps that are cancerous or could become cancerous, and to see the general health of your intestine. In order for the doctor to get the best look at the colon, adequate preparation is essential.

Why do cystic fibrosis patients need colonoscopies?

While the average lifetime risk for colorectal cancer is about 5 percent, the risk is 5-10 times higher for adults with CF.¹ Patients with CF should also start screening at 40 years of age instead of the recommended 50 years.¹ If you’ve received a solid organ transplant like a lung transplant, the risk of colorectal cancer is 20 times higher and screening should start even earlier, at the age of 30, but also depending on when the transplant was done.¹

Unique challenges of colonoscopy prep

The cystic fibrosis transmembrane conductance regulator (CFTR) gene that is defective in people with CF causes a buildup of thick and sticky mucus in various organs, including the lungs and colon. Stool is often thicker and stickier in those with CF than those who don’t have CF. This makes it more challenging to completely empty and cleanse the contents of the colon during colonoscopy prep.² It’s important to be properly cleaned out so that the doctor can get a good look at the colon and any polyps. If the prep is inadequate, you might be asked to repeat it so the doctor can take a second look.

If you have cystic fibrosis-related diabetes (CFRD), talk with your doctor about any specific diet or medication instructions they might have for you about the prep. They may make insulin adjustments, change or stop medications, or suggest a certain time of day for the colonoscopy.²

What does the colonoscopy prep involve for people with cystic fibrosis?

Individual details for your colonoscopy prep can vary depending on your personal health history and status and your insurance coverage. The specific instructions can vary, as well, so it’s important to ask your doctor for a detailed list of instructions on how to prep with CF. One example of a possible prep is here.³ There are some things that most people with CF tend to do with prep that you might want to keep in mind:²

• Split up the bowel cleansing solution into 3 groups of 64 ounces each; this is different from the general 2 groups of solution done by those without CF
• Drink multiple smaller washes instead of one big one; this is more manageable for you, and it also helps break down mucus build-up
• Drink the last of the solution 4-6 hours before the colonoscopy

You will also be asked to start a low-residue diet 3 days before the procedure. This means avoiding foods like raw vegetables, raw fruit, raisins or berries, granola, corn, brown or wild rice, and whole wheat bread and other products. You can still eat things like skinless potatoes, white bread or white rice, applesauce, chicken or turkey, bananas, cooked vegetables, and low-fiber cereals.³

Arrange for someone to drive you to and from the appointment. Most places won’t let patients drive themselves due to the medications used during the colonoscopy.

Tips for colonoscopy prep

Preparing for a colonoscopy can be arduous, and preparation is a bit more involved for those with cystic fibrosis. Here are some tips that might be helpful and make the process a little less unpleasant:²

• Refrigerating the prep solution can help with the taste, and chilling the glass you drink it in can help, as well
• You can request an unflavored bowel cleansing solution and add some lemon juice to it to improve the taste
• Drink the solution quickly; don’t sip it
• One 8-ounce glass every 10-15 minutes is a decent pace
• Drinking through a straw can help cut down on the salty taste
• After each solution, rinse your mouth with water, mouthwash, or clear soda
• Suck on hard candy or lollipops – but not ones with red or purple coloring

When to call the doctor

People with CF have a more intense preparation than those without CF, so it’s important to be mindful of your general health while prepping. Some weight loss or nausea are common, but there are some symptoms to be aware of that warrant calling the doctor, including:²

• Lightheadedness or fainting
• Severe nausea that keeps you from completing the prep
• If you have any symptoms longer than 48-72 hours after your colonoscopy like weight loss or dehydration, call your doctor.