Prospective, randomized trial comparing a new sodium phosphate-bisacodyl regimen with conventional PEG-ES lavage for outpatient colonoscopy preparation.

Background: Several recent trials have shown that colonoscopy preparation with sodium phosphate solution is as effective and at least as well tolerated as conventional PEG-ES lavage. These trials utilized two 1.5-fluid oz doses, one given on the evening before colonoscopy and the other early the next morning.

Methods: We devised a new sodium phosphate regimen in which the entire dose was given on the evening before examination (1.5 fl oz at 4 PM, 1.5-fl oz at 7 PM and 10 mg of bisacodyl at 10 PM) and performed a prospective, randomized trial that compared it with conventional PEG-ES lavage in terms of quality of colon cleansing, patient tolerance, and safety in an outpatient colonoscopy population with normal renal function. Seventy-two patients received sodium phosphate-bisacodyl and 75 PEG-ES lavage.

Results: The overall quality of colon cleansing and frequency of unsatisfactory preparations were similar with both methods. Patients found preparation with sodium phosphate-bisacodyl to be easier than PEG-ES lavage (p = 0.005). No clinically important adverse effects were seen with either method of preparation. The average cost of sodium phosphate-bisacodyl was $4.32 per patient compared with $18.15 for PEG-ES lavage preparation.

Conclusions: Preparation with sodium phosphate-bisacodyl, given on the evening before colonoscopy, is a well-tolerated, efficacious, and cost-effective alternative to conventional PEG-ES lavage.