Polyethylene glycol, or PEG, is the active ingredient in the GoLYTELY brand oral laxative. According to WebMD, the medication draws water into the colon to induce frequent, productive bowel movements in preparation for a colonoscopy, barium enema or similar procedure.
The medication comes packaged in powdered form and must be dissolved into one gallon of water prior to consumption. Although GoLYTELY is technically a laxative, the manufacturer's website states that this particular form of PEG is not necessarily intended to treat hard stools or infrequent bowel movements. Instead, doctors and surgeons prescribe GoLYTELY to cleanse the bowel as thoroughly as possible. Flushing the colon and intestines improves visibility, allowing medical professionals to diagnose intestinal disorders more accurately and less invasively.
The NuLYTELY website reports that patients who use this medication often experience slight nausea, cramping and bloating. Others report feelings of fullness that remain even after several bowel movements. Watery stools sometimes persist for between one and two hours after the last of the solution has been consumed. For optimal results, the patient must drink all of the solution unless directed otherwise by a physician or surgeon. After adding water to the powdered GoLYTELY, the patient begins drinking the liquid within a few hours. The manufacturer recommends storing the reconstituted liquid in a refrigerator to improve taste.