Lee-Robichaud, H., Thomas, K., Morgan, J., & Nelson, R.L. (2010). Lactulose versus polyethylene glycol for chronic constipation. Cochrane Database of Systematic Reviews, 7, CD007570.doi: 10.1002/14651858.CD007570.pub2
To identify and review all relevant data to determine whether lactulose or polyethylene glycol (PEG) is more effective in treating chronic constipation.
One hundred three initial references to January 24, 2008, were identified. A final set of 10 trials was included in this review. Studies were evaluated for various sources of bias and overall methodological quality. Trials were conducted in different countries in a variety of settings.
One study included a sample of patients on methadone maintenance, which may have some relevance for constipation associated with opioid use.