OpenClaim

Rifaximin Side Effects

The most commonly reported side effects of rifaximin include death, hospitalisation, and diarrhoea, based on 20,103 FDA adverse event reports from 2004 to 2025. 3.4% of reports found the drug to be ineffective.

Rifaximin side effects

Percentages show how often each reaction appears relative to total reports for rifaximin.

1
Death19.8%3,974
2
Hospitalisation8.5%1,703
3
Diarrhoea5.7%1,139
4
Off Label Use5.6%1,135
5
Therapy Interrupted4.9%989
6
Ammonia Increased4.1%824
7
Nausea3.9%777
8
Hepatic Encephalopathy3.8%757
9
Fatigue3.8%756
10
Confusional State3.5%707
11
Drug Ineffective3.4%693
12
Inability To Afford Medication3.4%679
13
Hepatic Cirrhosis3.2%653
14
Insurance Issue3.1%623
15
Fall3.0%601

These are voluntary reports and do not establish that rifaximin caused these reactions.

Report severity

77.9%Serious15,668 reports
39.3%Hospitalizations7,910 reports
29.3%Fatal5,896 reports

Seriousness is determined by the reporter, not by OpenClaim.

Rifaximin drug interactions

Other drugs that appear in adverse event reports alongside rifaximin. Drugs flagged as a suspected cause appear in the first column. Drugs taken at the same time but not suspected appear in the second.

Also suspected

1
Lactulose2.5%511
2
Sofosbuvir2.3%454
3
Ribavirin1.4%284
4
Adalimumab1.4%272
5
Teduglutide1.1%225
6
Furosemide0.9%190
7
Treprostinil0.9%181
8
Spironolactone0.9%180
9
Omeprazole0.8%168
10
Infliximab0.8%159
11
Sodium-oxybate0.8%158
12
Metronidazole0.8%154
13
Ambrisentan0.7%143
14
Lenalidomide0.7%143
15
Esomeprazole0.7%142

Taken alongside

1
Lactulose17.8%3,578
2
Furosemide14.0%2,824
3
Spironolactone13.0%2,604
4
Omeprazole8.7%1,752
5
Pantoprazole-sodium8.7%1,745
6
Ergocalciferol8.0%1,613
7
Levothyroxine-sodium6.3%1,266
8
Acetaminophen6.0%1,210
9
Insulin5.7%1,136
10
Ondansetron5.2%1,043
11
Gabapentin5.1%1,021
12
Aspirin4.5%906
13
Albuterol4.3%871
14
Folic-acid4.0%798
15
Oxycodone3.8%767

Co-occurrence in adverse event reports does not establish a drug interaction. Patients often take multiple medications, and these lists reflect prescribing patterns rather than causal relationships. Consult a healthcare provider about potential drug interactions.

Who reports rifaximin side effects

50.0% of rifaximin adverse event reports involve female patients and 45.7% involve male patients. The largest age group is elderly at 51%. These figures reflect who reports side effects, not underlying risk.

Sex

Female50.0%
Male45.7%
Unknown4.3%

Age group

< 20.2%
2–110.9%
12–170.6%
18–6447.2%
65+51.1%

What is rifaximin used for

Conditions and purposes for which patients were taking rifaximin when the adverse event was reported.

Abdominal DiscomfortAbdominal DistensionAbdominal InfectionAbdominal PainAbdominal Pain LowerAbdominal Pain UpperAbdominal RigidityAccidental OverdoseAcute DiarrheaAcute Hepatic FailureAcute On Chronic Liver FailureAdverse EventAlanine Aminotransferase IncreasedAlcoholic Liver DiseaseAlpha-1 Anti-trypsin Deficiency

Showing 15 of 503 indications

Rifaximin brand names and reporting trend

Rifaximin is sold under the brand name Rifaximin.

Brand names

Rifaximin5,059

Quarterly reports (20042025)

20052010201520202025

An upward trend reflects increased FAERS reporting overall, not necessarily increased risk.

Taking rifaximin with another medication?

Ask OpenClaim about your specific drug combination. Get a sourced report using FDA data, drug labels, and medical literature.