Low-dose amitriptyline is a safe and effective second-line treatment for moderate to severe irritable bowel syndrome, according to UK doctors behind the first trial of its kind conducted entirely in primary care.

The University of Leeds–led team said the tricyclic antidepressant was superior to placebo for relieving irritable bowel syndrome (IBS) symptoms in adults who failed to respond to dietary changes, fibre supplements and other first-line therapies.

They concluded that GPs could safely prescribe the treatment “with appropriate support to guide patient-led dose titration”.

Their phase III superiority trial included 463 patients (mean age 49) recruited from 55 general practices who were randomly assigned to amitriptyline once-daily 10mg, with dose titration over three weeks up to 30mg based on symptoms and tolerability, or placebo for 6-12 months.