The trial compares Laxabon® 4L versus Pursennid® Ex-Lax 36mg and 2L Laxabon® for large bowel cleansing prior to colonoscopy allocating patients planned for colonoscopy to one of the two cleansing regimens.

Effective large bowel cleansing prior to colonoscopy is still not achieved in all cases that undergo the procedure. The use of balanced electrolyte-polyethylene glycol (PEG) solution have improved the cleansing results and shortened the time needed for preparing the bowel. The problem with using PEG solution alone is the relatively large volume of the solution that the patients need to drink. The recommendation is to drink the solution until diarrhea fluid is clear and often 4 L or more is needed. Many patients refuse to drink the sufficient volume needed to get a clean colon. The large volume load can be a risk to patients suffering from renal and/or heart insufficiency.

Good results of bowel cleansing have also been reported with sodium phosphate solution or tablets. The fluid volume needed to drink along with sodium phosphate is generally no problem but this regimen causes electrolyte disturbances that usually are subclinical and of no significance but in patients with renal or heart insufficiency the sodium phosphate is contraindicated due to the risk of serious electrolyte disturbances.

Several combinations of stimulant laxatives with PEG solution have been tested before and the actual combination has been compared in one randomized study(1). Low-volume PEG plus sennosides preparation was better tolerated but it was not as effective as standard large-volume PEG.

PEG solution (Laxabon®) 4L is used for large bowel cleansing in many centers in Sweden and is the standard regimen used in our colonoscopy unit. In this study we compare this standard regimen with senna glycoside (Pursennid® Ex-Lax) 36mg (tablets) taken orally in the night before the colonoscopy and 2L Laxabon® solution orally starting to drink the solution four hours prior to the colonoscopy.

The result of large bowel cleansing is evaluated during the colonoscopy according to two separate validated scoring methods (Aronchick and Ottawa scores). Abdominal symptoms, discomfort, subjective grading of how hard/easy it was to complete the cleansing program and extra costs are evaluated with questionnaires.

Inclusion Criteria:

• Patient scheduled to undergo elective complete colonoscopy as an outpatient
• Age 18 or older
• The patient gives written informed consent and can understand the information given
• The patient can participate only once in the study

Exclusion Criteria:

• Earlier resection of the large bowel or rectum
• Active known colitis
• Ileus or gastro-intestinal obstruction