MedHelp says :
Golytely - What is polyethylene glycol electrolyte solution?
Polyethylene glycol electrolyte solution is a laxative solution that increases the amount of water in the intestinal tract to stimulate bowel movements. This medication also contains potassium, sodium, and other minerals to replace electrolytes that are passed from the body in the stool.
Polyethylene glycol electrolyte solution is used to clean the bowel before colonoscopy, a barium x-ray, or other intestinal procedures.
http://www.medhelp.org/drugs/show/1193