Factors Affecting Pre-Endoscopic Bowel Preparation

Bowel preparation for colonoscopy was designed as a means to improve the diagnostic and therapeutic accuracy and safety of the procedure. Adequate bowel preparation is important for a successful colonoscopy. The effectiveness of colonoscopy may limited by the particular circumstances of a person’s health such as age, pregnancy and comorbidities or even mental state that impede the ability to comply with the instructions for preparation of the bowel. Therefore, it is necessary for the endoscopic healthcare team to identify the specific conditions of the patient and to choose the suitable laxative agent. The purpose of this review is to explore the most efficient and safest bowel preparation for colonoscopy in individuals with underlying diseases, to reduce the frequency of inadequate preparation, adverse side effects, mis-diagnoses and suffering of the patient from the need to repeat the examination. For patients with diarrhea, renal failure, hepatic failure, heart problems, dehydration, bleeding, inflammatory bowel diseases, taking antihypertensive medications or are pregnant is safe and effective the use of polyethylenoglycol (PEG). For patients with diabetes, PEG with magnesium citrate or sodium phosphate (NaP) is recommended and for patients with constipation NaP or mosapride. Also, for the elderly before the administration of any laxative, biochemical tests should be done. PEG is the gold standard bowel preparation in patients with underlying diseases. Administration of NaP should be done with caution taking into account its absolute contraindications. The bowel preparations have not been adequately studied in special populations, while there is a need to develop new and more efficient preparation drugs with improved tolerability and reduced side-effects. The selection of a laxative agent should be tailored to each individual, taking into account the underlying disease and patient preference.