What alternatives are available for bowel prep in a patient with hematochezia and PEG intolerance?

From the Guidelines

The patient should be offered alternative bowel preparation options such as sodium picosulfate/magnesium citrate (Prepopik) or sodium sulfate, potassium sulfate, and magnesium sulfate (SUPREP) due to his inability to ingest polyethylene glycol (PEG) and his high-risk profile for colon cancer. Given the patient's family history of colon cancer and current symptoms of blood in stool, a colonoscopy is essential for proper evaluation and diagnosis. The patient's difficulty in ingesting PEG due to vomiting necessitates the use of alternative preparations that are better tolerated and require less fluid intake. Options like Prepopik, which requires drinking less fluid, typically one 5-ounce glass followed by five 8-ounce glasses of clear liquid, or SUPREP, which involves drinking two 6-ounce doses each followed by 32 ounces of water, can be considered 1. Additionally, magnesium citrate is also available over-the-counter and requires drinking 10 ounces followed by 64 ounces of clear liquid. For patients with severe difficulties, a "split-dose" regimen might be more tolerable, dividing the preparation between evening and morning, as recommended by the US Multi-Society Task Force on Colorectal Cancer 1. Low-volume preparations are particularly helpful for patients with swallowing difficulties or aversion to large fluid volumes, making them suitable alternatives for this patient.

The selection of a bowel-cleansing regimen should take into consideration the patient’s medical history, medications, and, when available, the adequacy of bowel preparation reported from prior colonoscopies, as stated in the recommendations from the US Multi-Society Task Force on Colorectal Cancer 1. Given the patient's symptoms and family history, completing a colonoscopy is crucial for proper evaluation, as blood in stool combined with family history of colon cancer represents significant risk factors requiring thorough investigation. The use of alternative bowel preparations can facilitate the completion of the colonoscopy, thereby ensuring that the patient receives the necessary diagnostic evaluation and subsequent care.

Some key points to consider when choosing an alternative bowel preparation include:

• The patient's ability to tolerate the preparation
• The volume of fluid required
• The presence of any medical conditions that may affect the choice of preparation
• The patient's preference and adherence to the preparation regimen
• The availability of the preparation and any necessary prescriptions or over-the-counter purchases.

By considering these factors and selecting an appropriate alternative bowel preparation, the patient can undergo a successful colonoscopy, which is essential for the diagnosis and management of his condition, given his high-risk profile for colon cancer 1.

From the FDA Drug Label

In both studies, sodium picosulfate, magnesium oxide and anhydrous citric acid was non-inferior to the comparator. The comparator was a preparation containing two liters of polyethylene glycol plus electrolytes solution (PEG + E) and two 5-mg bisacodyl tablets, administered the day before the procedure The primary efficacy endpoint was the proportion of patients with successful colon cleansing, as assessed by blinded colonoscopists using the Aronchick Scale Successful colon cleansing was defined as bowel preparations with >90% of the mucosa seen and mostly liquid stool that were graded excellent (minimal suctioning needed for adequate visualization) or good (significant suctioning needed for adequate visualization) by the colonoscopist

Alternative to Polyethylene Glycol (PEG): Sodium picosulfate, magnesium oxide, and anhydrous citric acid is a suitable alternative for patients who cannot ingest PEG.

• Key Points:
  • Non-inferior to PEG in colon cleansing
  • Can be administered in two dosing regimens: Split-Dose or Day-Before
  • Patients should be limited to a clear liquid diet on the day before the procedure
• Efficacy: Demonstrated successful colon cleansing in both adult and pediatric patients (9 to 16 years of age) 2 2

From the Research

Alternatives to Polyethylene Glycol (PEG) for Bowel Preparation

The patient is seeking alternatives to polyethylene glycol (PEG) due to difficulty ingesting it. Several studies have investigated alternative bowel preparation agents, including sodium picosulfate/magnesium citrate.

• Sodium picosulfate/magnesium citrate has been shown to be an effective and well-tolerated colorectal cleansing agent in adults and children 3, 4, 5, 6.
• It is available in a smaller volume than traditional PEG preparations, which may improve patient compliance 4, 6.
• Studies have compared sodium picosulfate/magnesium citrate to PEG and found it to be non-inferior in terms of bowel cleansing efficacy 4, 5, 6.
• Sodium picosulfate/magnesium citrate has also been shown to have a better tolerability and acceptability profile compared to PEG 5, 6.

Considerations for the Patient

Given the patient's difficulty ingesting PEG and their family history of colon cancer, it is essential to find an effective and tolerable alternative for bowel preparation.

• The patient's age and medical history should be taken into consideration when selecting an alternative bowel preparation agent 7.
• The patient's ability to ingest and tolerate the alternative agent should be assessed, and instructions on how to take the agent should be provided clearly 4, 5, 6.

Available Alternatives

Based on the available evidence, sodium picosulfate/magnesium citrate is a viable alternative to PEG for bowel preparation.

• Other alternatives, such as ascorbic acid-enriched PEG solution plus bisacodyl, may also be considered, but their efficacy and tolerability profiles may vary 4.
• The choice of alternative bowel preparation agent should be based on the patient's individual needs and medical history, as well as the availability of the agent 7.