Background: Adequate bowel cleansing is essential in achieving a good quality colonoscopy. However,
one of the barriers to achieving high-quality bowel cleansing is the patient's tolerability. Different bowel preparations
have been developed to improve tolerability while maintaining adequate bowel cleansing.
Objectives: We aim to explore the pros and cons of commonly used bowel preparations, particularly highlighting the
new ultra-low volume bowel preparation.
Methods: Extensive literature search was carried out on various databases to evaluate the effectiveness and side
effects of different bowel cleansing agents, including findings of recent clinical trials on ultra-low bowel preparation.
Results: Polyethylene glycol (PEG) has been commonly used as a bowel prep. Due to its high volume required to
ingest to achieve an adequate effect, it has been combined with various adjuncts to reduce the volume to make it
more tolerable. Magnesium and phosphate-based preps can achieve low volume, but they can be associated with
multiple side effects, mainly electrolyte disturbances. Ultra low volume prep (NER1006) was achieved by combing
PEG with ascorbic acid, and its efficacy and side effects were demonstrated in three noninferiority studies.
Conclusion: It is important to consider patient preferences, co-morbidities and tolerability, and efficacy and side
effect profiles when choosing bowel prep for patients undergoing colonoscopy. New ultra-low bowel prep showed
promising results in initial clinical trials, but further real-world post-marketing data will inform its value in clinical