Guidelines of The American Society of Colon and Rectal Surgeons published in Diseases of the Colon and Rectum state that the use of osmotic laxatives, such as polyethylene glycol and lactulose, is appropriate for non-operative management of constipation. Based on rate-quality evidence, both polyethylene glycol and lactulose has been strongly recommended as commonly used osmotic laxatives with proven safety and efficacy, in treating chronic constipation. The paper also described a meta-analysis including 10 randomized controlled trials comparing lactulose and polyethylene glycol in the management of chronic constipation, which found that polyethylene glycol was better than lactulose in outcomes of stool frequency per week, stool form, relief of abdominal pain, and the need for additional product use. Therefore, it was inferred that polyethylene glycol should be preferred to lactulose in the treatment of chronic constipation. It was also reported that long-term effects of chronic stimulant laxatives has not been confirmed and there remains a paucity of quality data regarding many other commonly used agents, such as milk of magnesia, senna, and stool softeners, for managing chronic constipation.