Adverse events with bismuth salts for Helicobacter pylori eradication: Systematic review and meta-analysis

Table 2 Crude adverse event rates, and relative risk of adverse events

Adverse event	Number of trials	Total number of patients	Number of patients in bismuth arms	Number of patients in comparison arms	Number of adverse events in bismuth arms (%)	Number of adverse events in comparison arms (%)	Relative risk of adverse events with bismuth versus comparison regimen (95% CI)
Any	25	3180	1585	1595	431 (27.2)	419 (26.3)	1.01 (0.87-1.16)
Abdominal pain	13	2439	1221	1218	63 (5.2)	61 (5.0)	1.06 (0.64-1.74)
Dark stools	4	467	233	234	39 (16.7)	5 (2.1)	5.06 (1.59-16.12)
Diarrhoea	22	3406	1761	1645	124 (7.0)	113 (6.9)	1.01 (0.72-1.42)
Dizziness	8	1630	867	763	54 (6.2)	49 (6.4)	1.18 (0.81-1.72)
Headache	14	2433	1276	1157	41 (3.2)	28 (2.4)	1.31 (0.81-2.11)
Metallic taste	14	2475	1260	1215	124 (9.8)	116 (9.6)	1.02 (0.81-1.28)
Nausea and/or vomiting	20	3417	1767	1650	111 (6.3)	86 (5.2)	1.16 (0.89-1.52)
Leading to withdrawal of therapy	28	3951	2033	1918	33 (1.6)	38 (2.0)	0.86 (0.54-1.37)