In bowel preparation using split dose PEG, various adjuncts to colonic cleansing were proposed to improve colonic preparation cleansing. Prokinetics, as an adjunct, was included in a few studies. The investigators study was to show that sufficient dosage of prokinetics added to split dose of PEG improves the state of bowel preparation.

This was a randomized, prospective, endoscopist-blinded clinical trial in which the efficacy of prokinetics coadministrated with split dose PEG on the bowel cleansing was inspected.

Endoscopists, who were blinded to the study group of the patient, immediately completed the Ottawa scale and the fluidity scale after procedure

Inclusion Criteria:

• Patient who are scheduled for colonoscopy

Exclusion Criteria:

• pregnancy,
• breast feeding,
• known or suspected bowel obstruction, and
• known allergy to PEG or Itopride ,
• presence of severe illness(renal failure, congestive heart failure, liver failure,), and
• refusal of consent to participate in the study