Polyethylene Glycol (PEG) is a substance with well-established, scientifically validated use in supporting the rectum and overall lower gastrointestinal system, specifically for the treatment of constipation. PEG acts as an osmotic laxative, meaning it retains water in the stool, resulting in softer feces and stimulating bowel movements. Its effectiveness and safety have been extensively studied in both adults and children for short- and long-term management of constipation, including chronic idiopathic constipation and constipation associated with irritable bowel syndrome.

Multiple randomized controlled trials and systematic reviews have demonstrated that PEG is more effective than placebo and often superior to other laxatives such as lactulose for increasing stool frequency, improving stool consistency, and reducing straining. PEG is generally well-tolerated; common side effects include bloating and flatulence, but serious adverse events are rare. It is available over-the-counter in many countries and is recommended by clinical guidelines (e.g., American Gastroenterological Association, European Society for Pediatric Gastroenterology Hepatology and Nutrition) as a first-line treatment for chronic constipation.

In summary, the use of PEG to support the rectum via its laxative properties is strongly supported by high-quality scientific evidence, with a long track record of efficacy and safety in clinical practice.