Constipation is a common condition for which PEG 3350 is an established treatment and prucalopride has recently been approved for this indication.


To compare the efficacy, safety and impact on quality of life (QoL) of PEG 3350 plus electrolytes (PEG 3350+E) vs. prucalopride in females with chronic constipation (CC) in whom laxatives have previously failed to provide adequate relief.


In this single-centre, randomised, double-blind, double-dummy study, patients with CC [<3 spontaneous complete bowel movements (SCBM)/week] remained in a controlled environment and received either a 26 g split dose of PEG 3350+E (N = 120) or 1–2 mg prucalopride (N = 120) daily for 28 days following a 14-day run-in period. The primary endpoint was the proportion of patients having ≥3 SCBMs during the last treatment week.


Non-inferiority of PEG 3350+E to prucalopride was demonstrated in the per-protocol population [difference, 10.1% (66.67% vs. 56.52%), 97.5% lower confidence interval (CI) −2.7%, above the preset margin of −20%] and approached superiority in the modified intent-to-treat population (difference, 9.8%, 97.5% lower CI, −3.1%). Statistically significant differences in favour of PEG 3350+E were observed for most secondary variables (bowel movements, stool weight, consistency, time to next SCBM, patient perception of straining and completeness of defecation). Colonic transit time was dramatically reduced in both arms. Both treatments were well tolerated.


PEG 3350+E was at least as effective as and generally better tolerated than prucalopride as a treatment for chronic constipation in this study population (NCT01251822;