Comparison of bisacodyl and sodium picosulphate in the treatment of chronic constipation

Background: Chronic constipation is a widespread condition. Although laxatives are generally accepted as being effective treatments, few studies have made formal comparisons of their efficacy and safety in chronic use. Objective: To compare the safety and efficacy of bisacodyl and sodium picosulphate in the treatment of chronic constipation over a 4-week period. Methods: Patients with chronic constipation (N = 144), recruited from out-patient clinics, were analysed for safety and efficacy in this open-label, randomised, parallel-group study. Patients were treated daily for 4 weeks (bisacodyl, 5-10 mg daily: 70 patients; sodium picosulphate, 5-10 mg daily: 74 patients). Primary efficacy criteria consisted of the number of bowel movements and stool consistency. Secondary efficacy criteria were straining at stool and physicians' global efficacy assessment. Safety assessments included adverse event monitoring, tolerability and changes in laboratory parameters. Results: Both treatments were equally effective in treating chronic constipation, providing sustained improvement in symptoms. Compared to baseline, there were significant (p < 0.001) improvements in stool frequency and consistency and in the occurrence of straining at 14 and 28 days for both treatment groups. Based on the physicians' global assessment, a significant improvement was observed in 74.6% (bisacodyl) and 79.2% (sodium picosulphate) of patients. Neither treatment had significant effects on serum electrolytes. There was a trend for better tolerability in patients receiving bisacodyl treatment based on the number of drug-related adverse events (bisacodyl: 7; sodium picosulphate: 14, two patients withdrawn). Conclusions: Bisacodyl and sodium picosulphate are equally well tolerated and effective in the treatment of chronic constipation over a 4-week period.