Frequently Asked Questions (FAQ)

What is bowel preparation?

Bowel preparation is the process of preparing your bowel for an effective diagnostic or therapeutic medical procedure such as colonoscopy or surgical procedure such as colon resection.

Why is adequate bowel preparation important?

Adequate bowel preparation is the key to a successful colonoscopy. It allows your provider to see the mucosal lining of your colon.

For the individual, inadequate bowel prep means aborted procedures, repeat procedures, reduced detection of polyps and cancer, increased risk for complications, lost co-pays and cost of transportation, lost day at work and wages, lost productivity for patient and accompanying adult.

For the healthcare system, inadequate bowel prep means longer procedure time and increased use of resources.

For the society, inadequate bowel prep means increased healthcare cost, lost productivity and opportunity cost, and increased morbidity and mortality from colorectal cancer.

What are the bowel preparation agents approved by the FDA?

Colyte (Alaven), GoLYTELY (Braintree), NuLYTELY (Braintree), TriLyte (Alaven), HalfLytely (Braintree), MoviPrep (Salix), SUPREP (Braintree), OsmoPrep (Salix), Visicol (Salix), Prepopik (Ferring). Even though, MiraLax is not FDA-approved for bowel preparation, it is approved for constipation and is widely used for bowel preparation.

What is the best bowel preparation agent?

The best bowel preparation agent is the one you can take. There are many bowel prep agents in the market. Often, your medical history and health insurance will dictate the type of bowel prep agent you can have. Regardless of the type you are given, a split regimen is superior to a night before regimen.

How do I follow the split dose regimen for bowel preparation?

Take half the total dose of your purgative the night before your colonoscopy. This is usually between 6-8PM. Make sure to take plenty of fluids throughout the day in addition to the fluids used for your bowel preparation. You need to stay hydrated throughout the process.

The second half of your prep should be started 4-6hours before the time of your colonoscopy. Be sure to finish it at least 2hours before your procedure time.

What is the right diet for bowel preparation?

Most providers recommend a clear liquid diet a day before your colonoscopy.

If you had a poor bowel prep before, you may need to be on low fiber diet 72 hours before your colonoscopy and clear liquid diet 24hrs before your colonoscopy OR clear liquid diet for 48hrs before your colonoscopy.

What is clear liquid diet?

Clear liquid diet excludes red and purple colored substances. Alcohol is also not allowed. Examples of clear liquid diet include water, tea, plain coffee, lemonade from powdered mix, carbonated beverages and soda, clear juices such as apple and white grape, plain or flavored gelatin, sports drinks such as Gatorade® , All-Sports®, Powerade®; sorbet, popsicles, honey, sugar, hard candy, fat-free broth, bouillon or consommé.

What is low residue (or low fiber) diet?

Residue refers to undigested food or fibers that make up part of the stool. A low residue diet reduces the frequency and volume of stool while prolonging the time it takes food to travel the intestine. You should avoid the following food items: whole wheat breads, cereals, crackers and rolls; whole wheat pasta, brown or wild rice; any item with nuts, seeds and fruits; buckwheat, granola, cornbread, pumpernickel bread; tough meat and meat items with skin; raw fruits, prunes and prune juice, berries, raisins and dried fruits; raw or partially cooked vegetables. You should also avoid milk and milk products.

If you are on a low residue diet, you may be allowed to have white bread, rolls and biscuits; white rice or noodles; plain crackers, potato rolls, skinless cooked potato; skinless chicken, skinless turkey, fish and other sea food; canned fruits without seeds or skin; eggs; vanilla wafers.

What are the possible side effects from bowel prep agents?

Though rare, the following adverse reactions have been reported. Abdominal fullness and cramping, nausea, vomiting, electrolyte abnormalities, cardiac arrhythmias, seizures, and renal impairment. If you have nausea or start vomiting, stop drinking for 30-45 minutes until the symptoms subside, then you may resume. Some people require anti-nausea medications. You will have diarrhea so stay near a toilet. Use a soft toilet tissue. For anorectal irritation or discomfort, use baby wipes, hydrocortisone cream or hemorrhoidal agents. You may call your provider at anytime if you feel very uncomfortable or sick.

Can I tell if I my bowel preparation is adequate for colonoscopy?

Your rectal effluent or stool after finishing your bowel prep agent can act as a guide. Your stool should be clear, yellow, light and liquid. The presence of dark particles or thick brown or black stool means you are not ready for colonoscopy. If your stool is not clear after taking your entire bowel prep agent, you may need additional prep agent.

What medications should I discuss with my provider before bowel preparation?

In general, your provider should be aware of all your medications before your colonoscopy. You should STOP taking fiber supplements and fish oil 2-3 days before your scheduled colonoscopy. If you take any of these medications, discuss with your provider one week before your scheduled colonoscopy. Some of these medications may need to be stopped or their dosages adjusted prior to your colonoscopy and during your bowel preparation.

  1. Anti-inflammatory medications like Ibuprofen, Advil, Motrin, Aleve, Naprosyn, and Naproxen.
  2. Antiplatelet medications like aspirin, Clopidrogel (Plavix), Ticlopidine (Ticlid), Prasugrel (Effient), Ticagrelor (Brillinta), Dipyridamole (Persantine), Aggrenox (dipyridamole plus aspirin), Abciximab (ReoPro)
  3. Anticoagulants like Coumadin or Warfarin, Rivaroxaban (Xarelto), Apixaban (Eliquis), Dabigatran (Pradaxa), Bivalirudin (Angiomax), Argatroban, Enoxaprin (Lovenox), Dalteparin (Fragmin), Tinzaparin (Innoprin), Fondaparinux (Arixtra).
  4. Hypoglycemic agents like insulin, metformin, glyburide, glipizide, glimepiride, acarbose, miglitol, voglibose, Pioglitazone (Actos), Rosiglitazone (Avandia), Exenatide (Byetta), Liraglutide (Victoza), sitagliptin (Januvia).

This list is by no means exhaustive. Tell your provider all the medications you take including over the counter and herbal supplements.

How can I make my bowel preparation agent (laxative) taste better OR less awful?

Bowel preparation agents often taste bad. Generally, sulfate containing formulas (e.g. GoLYTELY, and Colyte) are less palatable compared to non-sulfate containing formulas (e.g. NuLYTELY, and TriLyte). To improve their taste, some prep agents come in flavored packs e.g. NuLYTELY (flavors: cheery, lemon-lime, orange, pineapple), TriLyte (flavors: cherry, citrus-berry, lemon-lime, orange, pineapple), and HalfLytely (flavor: lemon-lime)

To improve taste, the following have been suggested:

  1. Chill the bowel cleansing liquid by putting it in a fridge or ice bucket.
  2. Use straw. Sipping is better than gulping.
  3. Add flavor. You can add lemon juice, lemon slices or sugar free flavor enhancers like Crystal Light®.
  4. Sugar free menthol-candy. Suck on menthol candy (e.g. Halls menthol candy) during ingestion of the bowel prep solution.

What can I do to make my bowel preparation better? My last colonoscopy was a “poor prep”

The solution to a “poor prep” resides in the reason for the poor prep. Ask yourself these questions?

  1. Did I follow the instructions? If not, why? Was it confusing? Was it inadequate? Was it presented in a language or format you understand? You should receive bowel prep instructions in the language you understand. You may need visual aids in brochures to improve your understanding. You may benefit from an instructional video on bowel prep. If you forgot your instructions, you may benefit from reminders such as stickers posted on easily seen items, use of a person to remind you or apps that can be downloaded on smart phones and tablets. Examples of such apps include Colonoscopy
  2. Do you have any risk factor for inadequate bowel preparation? These include medical conditions such as obesity, diabetes mellitus, chronic constipation, use of constipating medications such as opioid narcotics, psychotropic agents, prior resection of the colon, stroke, dementia, cirrhosis, prior abdominal surgeries such as hysterectomy and appendectomy, and history of prior inadequate bowel prep. If the answer is yes. You may need additional intervention such as being on a low fiber diet for 72 hours prior to your colonoscopy, being on a clear liquid diet for 24-48hrs prior to your colonoscopy, use of laxative adjuncts such as bisacodyl or magnesium citrate in addition to your bowel prep agent. You may also require large volume agents such as GoLYTELY instead of low volume agents such as MoviPrep.

Why should I avoid red or purple colored drinks and food?

These food items may resemble blood in the colon and confuse your provider.

Why should I avoid seeds and nuts prior to colonoscopy?

These foods are hard to digest and may remain in your colon. They are hard to wash out of the colon and may clog the instruments used for colonoscopy (scope).

Why can’t I drive or go to work after my colonoscopy?

Sedation during colonoscopy impairs judgment, memory and reflexes. You should have someone to take you home after colonoscopy. You may return to work or drive the day after your colonoscopy.

I already have diarrhea before starting my bowel prep, do I still need to do bowel prep?

Yes. You still need bowel preparation prior to your colonoscopy. Your intestine continue to produce waste materials even with diarrhea. It is important to have a clean colon during your colonoscopy.

My stool is watery and clear, do I still need to drink the entire bowel prep     solution?

Yes.  Drinking your entire prep solution ensures complete cleaning of your colon.

Can I do bowel prep and colonoscopy while I am having my period (menstruation)?

Yes. Bowel preparation and colonoscopy are safe during menstruation.

I have drank a lot of prep solution and haven’t gone to the bathroom…. Do I continue? How long does it take to work?

Yes, continue drinking. You will eventually have a bowel movement. Time to bowel movement varies. Some people have bowel movement within minutes while others take hours. Make sure you drink the entire bowel prep solution. If you still have solid stools or brown stool or stool with particles after finishing your bowel prep, contact your physician.

Do I need to stop aspirin before colonoscopy?

No. Colonoscopy while on aspirin is safe. Patients that take aspirin for heart and blood vessel disease, can continue to do so before and after colonoscopy. Ask your doctor if he wants you to stop aspirin for other reasons.

Do I need to stop non-steroidal anti-inflammatory drugs (NSAIDS) like naproxen, ibuprofen, celebrex before colonoscopy?

No. Colonoscopy can be safely performed while on these medications. Your doctor may want you to stop these medications for other reasons.

Do I need to stop plavix before colonoscopy?

No. Depending on the planned intervention during colonoscopy and the reason for plavix use, plavix may need to be stopped for a few days prior to colonoscopy. Discuss use of plavix before colonoscopy with your doctor.

Is it okay to have sex a day before or after colonoscopy?

Yes, as long as your are doing fine.