Randomised controlled trials (RCTs) of medical therapies for constipation
| Drug class | Drug | Number of RCTs | Level of evidence and recommendation |
|---|---|---|---|
| Osmotic laxatives | Polyethylene glycol | 8 (5 placebo controlled) | Good evidence supports use; better than lactulose |
| Lactulose | 11 (3 placebo controlled) | Moderate evidence supports use | |
| Bulking agents | Psyllium | 9 (3 placebo controlled) | Moderate evidence supports use |
| Calcium polycarbophil | 1 (v psyllium) | Poor evidence for or against use | |
| Bran | 4 (1 placebo controlled) | Poor evidence for or against use | |
| Methylcellulose | 1 (v psyllium) | Poor evidence for or against use | |
| Softening or wetting agents | Dioctyl (docusate) calcium, dioctyl sodium | 4 (1 placebo controlled) | Poor evidence for or against use; psyllium better |
| Stimulant laxatives | Senna | 1 v sodium picosulfate; 1 v bran | Poor evidence for or against use |
| Bisacodyl | 1 v bisoxatin | Poor evidence for or against use | |
| Other agents | Tegaserod | 1 placebo controlled | Good evidence supports use |