Table 1.

Summary of evidence from trial-based meta-analyses and network meta-analyses concerning the efficacy of drugs for IBS

Patient group tested in	Drug and dose	Quality of data56	Adverse events56 84	Ranking according to network meta-analysis35 76 87
				Efficacy in terms of global symptoms (no. of RCTs and patients)	Efficacy in terms of composite endpoint (abdominal pain and bowel habit) (no. of RCTs and patients)	Efficacy in terms of abdominal pain (no. of RCTs and patients)	Efficacy in terms of bowel habit (no. of RCTs and patients)
Unselected patients with IBS	Soluble fibre (eg, ispaghula 6–30 g/day)	Moderate	Total adverse events no more common in three RCTs	Fourth (6 RCTs, 161 patients)	N/A	Fifth (2 RCTs, 125 patients)	N/A
	Antispasmodics (eg, hyoscine 20 mg t.i.d.)	Very low	Total adverse events significantly more common in a meta-analysis of 26 RCTs, particularly dry mouth, dizziness and blurred vision	Third (16 RCTs, 953 patients)	N/A	Second (10 RCTs, 549 patients)	N/A
	Peppermint oil 200 mg t.i.d.	Low	Total adverse events no more common in a meta-analysis of six RCTs	First (6 RCTs, 342 patients)	N/A	Third (4 RCTs, 260 patients)	N/A
	Tricyclic antidepressants (eg, amitriptyline 10–30 mg o.d.)	Moderate	Total adverse events significantly more common in a meta-analysis of six RCTs, particularly dry mouth and drowsiness	Second (10 RCTs, 376 patients)	N/A	First (4 RCTs, 92 patients)	N/A
	Selective serotonin re-uptake inhibitors (eg, fluoxetine 20 mg o.d.)	Low	Total adverse events no more common	Fifth (5 RCTs, 143 patients)	N/A	Fourth (5 RCTs, 131 patients)	N/A
Patients with IBS-C	Linaclotide 290 mcg o.d.	High	Diarrhoea significantly more common in a meta-analysis of three RCTs	First (4 RCTs, 2617 patients)	First (3 RCTs, 2447 patients)	First (3 RCTs, 2447 patients)	First (3 RCTs, 2447 patients)
	Lubiprostone 8 mcg b.i.d.	Moderate	Nausea significantly more common in a meta-analysis of three RCTs	Seventh (3 RCTs, 1271 patients)	Third (2 RCTs, 452 patients)	Fifth (2 RCTs, 452 patients)	N/A
	Plecanatide 6 mcg o.d.	Moderate	Diarrhoea significantly more common in a meta-analysis of two RCTs	Fifth (2 RCTs, 1461 patients)	Fifth (2 RCTs, 1461 patients)	Fourth (2 RCTs, 1461 patients)	Fifth (2 RCTs, 1461 patients)
	Tenapanor 50 mcg b.i.d.	Moderate	Rates of diarrhoea numerically higher	Fourth (3 RCTs, 1382 patients)	Second (3 RCTs, 1401 patients)	Second (3 RCTs, 1401 patients)	Third (3 RCTs, 1401 patients)
Patients with IBS-D or IBS-M	Alosetron 1 mg b.i.d.	High	Constipation significantly more common in a meta-analysis of three RCTs	First (2 RCTs, 1154 patients)	First (3 RCTs, 787 patients)	Third (6 RCTs, 2606 patients)	First (1 RCT, 280 patients)
	Eluxadoline 100 mg b.i.d.	Moderate	Rates of constipation, nausea and vomiting numerically higher in a pooled analysis of two RCTs	Fourth (4 RCTs, 2312 patients)	Third (4 RCTs, 2312 patients)	Fifth (4 RCTs, 2312 patients)	Sixth (4 RCTs, 2312 patients)
	Ramosetron 2.5 mcg o.d.	Moderate	Total adverse events no more common in a meta-analysis of five RCTs	Second (2 RCTs, 782 patients)	Second (1 RCT, 348 patients)	First (2 RCTs, 782 patients)	Fourth (2 RCTs, 782 patients)
	Rifaximin 550 mg t.i.d.	Moderate	Total adverse events no more common in a pooled analysis of three RCTs	Sixth (2 RCTs, 1260 patients)	Fifth (2 RCTs, 1260 patients)	Sixth (2 RCTs, 1260 patients)	Third (2 RCTs, 1260 patients)

b.i.d., two times per day; IBS, irritable bowel syndrome; IBS-C, IBS with constipation; IBS-D, IBS with diarrhoea; IBS-M, IBS mixed; o.d., once daily; RCTs, randomised controlled trials; t.i.d., three times per day.