Numerous randomized controlled trials demonstrate the efficacy and safety of polyethylene glycol 3350 for chronic idiopathic constipation. A new US Food and Drug Administration-recommended primary efficacy endpoint for evaluating chronic idiopathic constipation prompted a reevaluation by Menees SB. et al., of previously reported clinical data with polyethylene glycol 3350. 

Their study included adults with chronic idiopathic constipation and randomized them to receive either polyethylene glycol 3350 17 g (n = 204) or a placebo (n = 100) once daily for 24 weeks. They performed Post hoc analyses using the US Food and Drug Administration endpoint (≥3 complete spontaneous bowel movements/week and a rise of ≥1 complete spontaneous bowel movement/week from baseline for ≥9/12 weeks, including 3 of the last four weeks) along with additional efficacy and safety outcomes. 

They found that the proportion of patients meeting the new endpoint was markedly higher with polyethylene glycol 3350 vs. placebo (42% vs. 13%). Further, they found polyethylene glycol 3350 to be superior to placebo in terms of reductions in the mean number of hard/lumpy stools/week (–2.1 vs. –0.9) and the weekly mean five-point cramping rating (–0.3 vs. –0.1). The polyethylene glycol 3350 group also showed a marked decrease in the proportion of subjects with gastrointestinal adverse events after the first week of treatment. 

Thus, taking into account the current US Food and Drug Administration-recommended responder definition and other secondary outcomes, once-daily polyethylene glycol 3350 has substantial and sustained efficacy and safety over 24 weeks in patients with chronic idiopathic constipation. 

Menees SB, Lembo AJ, Chey WD. Polyethylene Glycol 3350 in the Treatment of Chronic Idiopathic Constipation: Post hoc Analysis Using FDA Endpoints. Canadian Journal of Gastroenterology and Hepatology.2022;2022. https://doi.org/10.1155/2022/3533504