Indirect chromoendoscopy is performed by providing a subject with an orally administered composition which includes indigo carmine dye mixed with polyethylene glycol (PEG). Preferably, the subject ingests at least 160 mg of indigo carmine prior to the endoscopic procedure. This is accomplished by ingesting 1 ml to 6 L of a premixed or reconstituted indigo carmine and PEG composition up to twenty four hours prior to the endoscopic procedure.