Colonoscopy is a medical procedure used to examine the inner lining of the large intestine (colon) and rectum. During a colonoscopy, a thin flexible tube (colonoscope) is inserted through the anus and advanced through the entire colon. Colonoscopy allows the physician to visually examine the entire colon and rectum to check for abnormal growths, inflamed tissue, ulcers, polyps, and cancer. In order to have a clear view of the colon during the procedure, the colon must be empty. Therefore, bowel preparation (cleansing) is required prior to the colonoscopy.

Bowel Preparation Medications

Several prescription and over-the-counter bowel preparation medications are commonly used to clear out the colon before a colonoscopy. The most commonly used prescription bowel prep drugs are:

Polyethylene Glycol (PEG): PEG-3350 (Colyte, GoLYTELY, NuLYTELY) is a clear liquid that works by causing diarrhea. It draws water into the intestine from surrounding tissues to flush out waste. PEG is very effective in cleansing the colon but has an unpleasant salty taste.

Sodium Picosulfate + Magnesium Citrate (Pico-Salax): This two-part prep cleanses the colon using a stimulant laxative (sodium picosulfate) and an osmotic laxative (magnesium citrate). It has the ability to flush waste from the colon through diarrhea. This preparation may cause abdominal discomfort, nausea, headache, and bloating.

Bisacodyl + sodium picosulfate + PEG (CitraFleet): CitraFleet has three active ingredients that work together to stimulate and flush the bowels. Bisacodyl acts as a stimulant laxative, sodium picosulfate is a stimulant laxative, and PEG draws water into the intestines causing diarrhea and cleansing of the colon. Though effective, its taste remains challenging for many patients.

Bisacodyl + PEG (Golytely): Golytely contains bisacodyl, a stimulant laxative along with PEG to cleanse the colon. Both ingredients work synergistically to stimulate and flush the bowels. However, the strong salty flavor of PEG is difficult to tolerate.

Commonly used over-the-counter bowel prep medicines include Oral Sodium Phosphate (Fleet), Magnesium Citrate and Bisacodyl tablets. Magnesium citrate works by drawing water into the intestines via osmosis and causing diarrhea to flush out waste. Bisacodyl is a stimulant laxative that irritates the intestinal lining to induce bowel movements.

Bowel Preparation Instructions

Regardless of the bowel preparation medication prescribed, proper adherence to the instructions is crucial for an effective colon cleansing. The typical bowel prep instructions involve:

Fasting from solid foods for 1-2 days before the colonoscopy and consuming only clear liquids. This allows the bowel prep medication to efficiently flush out stool from the empty colon.

Drinking the entire Colonoscopy Bowel Preparation Drugs prep solution over several hours, as directed by the physician. Most bowel preps involve drinking at least 4 liters of the prep solution along with adequate clear fluids. This provides the water and electrolytes needed for efficient cleansing.

Staying close to the toilet as the medication causes frequent, loose stools that resemble watery diarrhea. This emptying process usually begins within 30 minutes to 3 hours after starting the bowel prep.

Completing the entire bowel prep usually within 6-8 hours. The longer it takes to finish, the less effective the cleansing will be. Any remaining stool prevents a clear view of the colon during the procedure.

Timing the prep properly so that the colon is emptied within a few hours of the colonoscopy. This ensures the bowel is optimally clean at the time of the procedure.

Bowel Preparation Side Effects

While bowel cleansing is essential for an accurate colonoscopy, the process can cause temporary but uncomfortable side effects like:

– Abdominal cramps: The laxatives stimulate bowel motility which may cause abdominal pain, cramps or discomfort.

– Nausea and vomiting: Drinking large volumes of solution in a short time can irritate the stomach and lead to nausea, vomiting or gagging.

– Bloating: As the liquid draws water into the intestines it may cause abdominal fullness, gas and bloating.

– Dehydration: Frequent diarrhea can deplete water from the body leading to symptoms like lightheadedness, thirst and headache.

– Anal irritation: Repeated bowel movements may cause minor anal discomfort, pain or irritation.

– Sleep disturbances: Prepping overnight may disrupt sleep due to frequent toilet visits.

Usually, these side effects are temporary and resolve soon after the bowel preparation and colonoscopy are complete. Staying hydrated with extra clear fluids helps minimize side effects. Contact the doctor for severe or bothersome symptoms.

*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it