The purpose of this study to to see how well Miralax (PEG-3350) and Gatorade cleans the colon before a colonoscopy and how easy it is to take compared to Golytely (PEG-ELS) bowel preparation solution. Another purpose is to see if taking half of the bowel preparation solution on the evening before the colonoscopy and half on the morning of the colonoscopy will result in a cleaner colon than taking all of the bowel preparation solution on the evening before.

Inclusion Criteria:

• 18-80 years in age
• Undergoing full colonoscopy for colorectal cancer screening or colon polyp/cancer surveillance or other diagnostic purpose

Exclusion Criteria:

• Allergic to polyethylene glycol
• Pregnant or lactating
• Baseline abnormalities of relevant serum electrolytes including Sodium, Potassium, Calcium, Magnesium and phosphorus
• Congestive Heart Failure NY Heart Assn, Grades III and IV
• Liver Cirrhosis Childs Pugh Class B or C
• Serum Creatinine greater than 1.5
• Previous alimentary tract surgery
• Ongoing symptoms of abdominal pain, bloating, nausea or constipation
• Ileus, suspected bowel obstruction, toxic colitis or megacolon, severe ulcerative colitis