Optimum bowel cleansing before colonoscopy

This month's issue of the American Journal of Gastroenterology examines a dual-action, low-volume bowel cleanser administered the day before colonoscopy.

Optimal bowel preparation is vital for the efficacy and safety of colonoscopy.

The inconvenience, discomfort, required consumption of large volumes of product, and potential adverse effects associated with some bowel preparations deter patients from colonoscopy, and may provide inadequate cleansing.

A dual-action, non-phosphate, natural orange-flavored, low-volume preparation containing sodium picosulfate and magnesium citrate (P/MC) is being reviewed for bowel cleansing.

Dr Philip Katz and colleagues from Pennsylvania, USA reported that this was a phase 3, randomized, multicenter, assessor-blinded, prespecified non-inferiority, head-to-head study.

The team investigated the efficacy, safety, and tolerability of day-before administration of picosulfate and magnesium citrate vs 2L polyethylene glycol solution, and 2 5-mg bisacodyl tablets in adult patients preparing for colonoscopy.

The primary objective was to demonstrate the non-inferiority of picosulfate and magnesium citrate to 2L PEG-3350 and bisacodyl tablets in overall colon cleansing using a modified Aronchick scale.

The doctors also evaluated the efficacy in the ascending, mid, and recto-sigmoid segments of colon using a modified Ottawa scale.

Patient acceptability and tolerability of the bowel preparations were assessed via a standard questionnaire.

Adverse events related to the bowel preparation were reported by 1% of patients

American Journal of Gastroenterology

The research team assessed safety based on the monitoring of adverse events and meaningful findings on clinical evaluations including physical examinations, vital sign measurements, and electrocardiograms.

A total of 603 patients were randomized to receive either picosulfate and magnesium citrate or 2L PEG-3350 and bisacodyl tablets.

The team of doctors noted that based on the Aronchick scale, successful overall cleansing was similar in patients receiving picosulfate and magnesium citrate.

Patients receiving 2L PEG-3350 and bisacodyl tablets picosulfate and magnesium citrate demonstrated non-inferiority to 2L PEG-3350 and bisacodyl tablets in overall cleansing of the colon, as measured by the Aronchick scale.

Similarly, the efficacy of picosulfate and magnesium citrate , as measured by the Ottawa scale, was non-inferior to 2L PEG-3350 and bisacodyl tablets in cleansing the ascending, mid, and recto-sigmoid segments of the colon.

The researchers noted that patient-reported acceptability and tolerability for each item examined on the questionnaire was significantly greater for picosulfate and magnesium citrate compared with 2L PEG-3350 and bisacodyl tablets.

Treatment-emergent adverse events related to the bowel preparation reported by 1% of patients receiving picosulfate and magnesium citrate or 2L PEG-3350 and bisacodyl tablets were nausea, vomiting, and headache.

No clinically meaningful changes were noted in either treatment arm in data collected from physical examinations, vital sign measurements, and ECGs.

Dr Katz's team commented "When administered as a day-before dose, the bowel cleansing effects of picosulfate and magnesium citrate were non-inferior compared with 2L PEG-3350 and bisacodyl tablets using the clinician-rated Aronchick and Ottawa scales."

"Treatment acceptability was significantly more favorable in patients receiving picosulfate and magnesium citrate  than in patients receiving 2L PEG-3350 and bisacodyl tablets."