Multicenter, 4-week, double-blind, randomized, placebo-controlled trial of sodium picosulfate in patients with chronic constipation.

OBJECTIVES

Although it has been used as a laxative for many years, high-quality trials assessing the efficacy of the laxative sodium picosulfate (SPS) are lacking. The purpose of this study was to assess the efficacy and safety of 4-week treatment with SPS in patients with functional constipation as defined by the Rome III diagnostic criteria.

METHODS

This study was a randomized, double-blind, placebo-controlled, parallel-group study in 45 general practices in Germany. A total of 468 patients with chronic constipation presenting to their general practitioner and fulfilling the Rome III diagnostic criteria were screened. After a 2-week baseline period, 367 patients were randomized to either SPS drops or matching placebo in a 2:1 ratio for 4 weeks. Dose titration was permitted throughout treatment. Patients without a bowel movement for more than 72 h were allowed to use a "rescue" bisacodyl suppository. The primary end point was the mean number of complete spontaneous bowel movements (CSBMs) per week. A spontaneous bowel movement (SBM) was defined as a stool not induced by rescue medication, whereas a CSBM was defined as an SBM associated with a sensation of complete evacuation.

RESULTS

The mean number (+/-s.e.) of CSBMs per week increased from 0.9+/-0.1 to 3.4+/-0.2 in the SPS group and from 1.1+/-0.1 to 1.7+/-0.1 in the placebo group (P<0.0001). The percentage of patients reaching an increase of > or =1 in the mean number of CSBMs per week compared to baseline was 65.5% vs. 32.3%, respectively (P<0.0001). The percentage of patients reaching a mean number of at least three CSBMs per week was 51.1% in the SPS group and 18.0% in the placebo group (P<0.0001). After 24 h, approximately 69% of patients in the SPS group and 53% in the placebo group had their first SBM. The SPS dose was titrated down during the study by nearly 50% of patients. Assessment of quality of life (QoL) by the constipation-related Patient Assessment of Constipation (PAC)-QoL questionnaire showed significant improvement in SPS-treated patients compared to the placebo group.

CONCLUSIONS

Treatment of chronic constipation with SPS improves bowel function, symptoms, and QoL and is well tolerated. The dose can be adjusted individually while maintaining benefit.