Table 7.
Guidance on optimising the use of specific therapies.
| Which patients may benefit? | Time to achieve efficacy on key symptoms | Common adverse effects and management | |
|---|---|---|---|
| Advanced dietary strategies | |||
| Low-FODMAP diet | • After conservative dietary management strategies have failed • Used alongside pharmacological therapies | • Reduction in severity of overall GI symptoms within seven days55 • May take up to eight weeks for symptom response to appear if dietary-mediated changes to gut microbiota are the cause of the improvement64 | • Further research needed to determine if there are potential adverse effects on the gut microbiota associated with long-term use54,55 • Potential for inadequate nutrient intake with stringent dietary restriction54 |
| Therapies targeting constipation | |||
| Linaclotidea,34–36 | • Constipation, pain or bloating as the predominant symptom | • Improvement in bowel frequency seen as early as week 1 • Maximal effect on abdominal pain and bloating may take longer (8–10 weeks) | • Diarrhoea – usually resolves within seven days or with temporary cessation of treatment |
| Lubiprostone37 | • Constipation as the predominant symptom | • Improvements in bowel movement frequency, straining, constipation severity and stool consistency seen at month 1 • Improvements in abdominal pain and bloating seen at month 2 | • Diarrhoea and nausea • To limit dose-dependent nausea, should be taken with meals |
| Therapies targeting diarrhoea | |||
| Loperamideb | • Diarrhoea as the dominant symptom (for acute episodes) | • Can be used on an as-needed basis, but patients may take a fixed dose to avoid diarrhoea episodes | • Constipation (treatment should be stopped in severe cases) |
| Eluxadolinec,44 | • Diarrhoea, abdominal pain or bloating as the predominant symptom | • Significant improvement in abdominal pain and stool symptoms from week 1 onwards • Maximum effect on pain may take four to six weeks | • Constipation – can be minimised by avoiding concomitant use with other medicines that may cause constipation |
| Cholestyramine | • IBS-D with increased colonic bile acid • After other pharmacological therapies targeting diarrhoea have been tried | • Within one to three weeks • Stop after one to three months if the therapeutic effect is not adequate | • Should be started at a low dose and gradually increased to reduce the incidence and intensity of adverse effects such as nausea and upper GI symptoms47 • Can reduce the bioavailability of other drugs so should be taken at a different time of day |
| Ondansetron49 | • Mild to moderate symptoms of diarrhoea (not severe cases) | • Onset of effect within one week in most cases • Improves loose stools, frequency, and urgency | • Constipation (can be managed with dose reduction) |
| Rifaximin52,53 | • Bloating as the predominant symptom | • Significant relief of IBS symptoms, bloating, abdominal pain, and loose or watery stools after two weeks | • Antibiotic resistance of GI flora a concern if use widespread12 • Long-term efficacy uncertain – effect gradually disappears and re-treatment is necessary in a large proportion of patients to retain symptom improvement53 |
| Therapies targeting pain | |||
| Antispasmodics | • Pain as the predominant symptom (to provide symptomatic short-term relief) | • Effect on pain is usually immediate (within an hour) | • Use may be limited by anticholinergic adverse events12 |
| TCAs | • Patients with IBS-D • Patients with insomnia, anorexia, or weight loss | • Patients usually started at low doses to minimise the potential for side effects • If an effect is not seen within a month, the dose may be increased | • Constipation • Drowsiness, dry mouth • Side effects frequently develop as the dose is increased |
| SSRIs | • Patients with IBS-C • Patients with anxiety or depression | • Onset of therapeutic benefit seems to occur within the first three to four weeks (but may take up to eight weeks) | • Diarrhoea • Sleep disturbances • Nervousness |
a
EMA-approved for the symptomatic treatment of moderate to severe IBS-C.
b
EMA-approved for the symptomatic treatment of acute episodes of diarrhoea associated with IBS-D.
c
EMA-approved for the treatment of IBS-D.
All other treatments included in the table are not currently approved by the EMA for the management of IBS.
EMA: European Medicines Agency; FODMAP: fermentable oligosaccharides, disaccharides, monosaccharides and polyols; GI: gastrointestinal; IBS-C: irritable bowel syndrome with constipation predominance; IBS-D: irritable bowel syndrome with diarrhoea predominance; SSRIs: selective serotonin re-uptake inhibitors; TCAs: tricyclic antidepressants.