XIFAXAN SIDE EFFECTS

  • Generic Name: rifaximin
  • Brand Name: Xifaxan
  • Drug Class: Antibiotics, Other, Antidiarrheals
Last updated on MDtodate: 10/8/2022

SIDE EFFECTS

Clinical Studies Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

Travelers’ Diarrhea

The safety of XIFAXAN 200 mg taken three times a day was evaluated in patients with travelers’ diarrhea consisting of 320 patients in two placebo-controlled clinical trials with 95% of patients receiving three or four days of treatment with XIFAXAN. The population studied had a mean age of 31.3 (18-79) years of which approximately 3% were ≥65 years old, 53% were male and 84% were White, 11% were Hispanic.

Discontinuations due to adverse reactions occurred in 0.4% of patients. The adverse reactions leading to discontinuation were taste loss, dysentery, weight decrease, anorexia, nausea and nasal passage irritation.

The adverse reaction that occurred at a frequency ≥2% in XIFAXAN-treated patients (n=320) at a higher rate than placebo (n=228) in the two placebo-controlled trials of TD was:

  • headache (10% XIFAXAN, 9% placebo)
Hepatic Encephalopathy

The data described below reflect exposure to XIFAXAN in 348 patients, including 265 exposed for 6 months and 202 exposed for more than a year (mean exposure was 364 days). The safety of XIFAXAN 550 mg taken two times a day for reducing the risk of overt hepatic encephalopathy recurrence in adult patients was evaluated in a 6-month placebo-controlled clinical trial (n=140) and in a long term followup study (n=280). The population studied had a mean age of 56 (range: 21 to 82) years; approximately 20% of the patients were ≥65 years old, 61% were male, 86% were White, and 4% were Black. Ninetyone percent of patients in the trial were taking lactulose concomitantly. The most common adverse reactions that occurred at an incidence ≥5% and at a higher incidence in XIFAXAN-treated subjects than in the placebo group in the 6-month trial are provided in Table 1.

Table 1: Most Common Adverse Reactions in HE Trial

MedDRA Preferred Term Number (%) of Patients
XIFAXAN Tablets 550 mg TWICE DAILY
n=140
Placebo
n=159
Peripheral edema 21 (15%) 13 (8%)
Nausea 20 (14%) 21 (13%)
Dizziness 18 (13%) 13 (8%)
Fatigue 17 (12%) 18 (11%)
Ascites 16 (11%) 15 (9%)
Muscle spasms 13 (9%) 11 (7%)
Pruritus 13 (9%) 10 (6%)
Abdominal pain 12 (9%) 13 (8%)
Anemia 11 (8%) 6 (4%)
Depression 10 (7%) 8 (5%)
Nasopharyngitis 10 (7%) 10 (6%)
Abdominal pain upper 9 (6%) 8 (5%)
Arthralgia 9 (6%) 4 (3%)
Dyspnea 9 (6%) 7 (4%)
Pyrexia 9 (6%) 5 (3%)
Rash 7 (5%) 6 (4%)
* reported in ≥5% of Patients Receiving XIFAXAN and at a higher incidence than placebo

 

Irritable Bowel Syndrome With Diarrhea

The safety of XIFAXAN for the treatment of IBS-D was evaluated in 3 placebo-controlled studies in which 952 patients were randomized to XIFAXAN 550 mg three times a day for 14 days. Across the 3 studies, 96% of patients received at least 14 days of treatment with XIFAXAN. In Trials 1 and 2, 624 patients received only one 14-day treatment. Trial 3 evaluated the safety of XIFAXAN in 328 patients who received 1 open-label treatment and 2 double-blind repeat treatments of 14 days each over a period of up to 46 weeks. The combined population studied had a mean age of 47 (range: 18 to 88) years of whom approximately 11% of the patients were ≥65 years old, 72% were female, 88% were White, 9% were Black and 12% were Hispanic.

The adverse reaction that occurred at a frequency ≥2% in XIFAXAN-treated patients at a higher rate than placebo in Trials 1 and 2 for IBS-D was:

  • nausea (3% XIFAXAN, 2% placebo)

The adverse reactions that occurred at a frequency >2% in XIFAXAN-treated patients (n=328) at a higher rate than placebo (n=308) in Trial 3 for IBS-D during the double-blind treatment phase were:

ALT increased (XIFAXAN 2%, placebo 1%)

  • nausea (XIFAXAN 2%, placebo 1%)
Less Common Adverse Reactions

The following adverse reactions, presented by body system, were reported in less than 2% of patients in clinical trials of TD and IBS-D and in less than 5% of patients in clinical trials of HE:

Hepatobiliary disorders: Clostridium colitis

Investigations: Increased blood creatine phosphokinase

Musculoskeletal and connective tissue disorders: myalgia

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of XIFAXAN. Because these reactions are reported voluntarily from a population of unknown size, estimates of frequency cannot be made. These reactions have been chosen for inclusion due to either their seriousness, reported in ≥5% of Patients Receiving XIFAXAN and at a higher incidence than placebo frequency of reporting or causal connection to XIFAXAN.

Infections And Infestations

Cases of C. difficile-associated colitis have been reported.

General

Hypersensitivity reactions, including exfoliative dermatitis, rash, angioneurotic edema (swelling of face and tongue and difficulty swallowing), urticaria, flushing, pruritus and anaphylaxis have been reported. These events occurred as early as within 15 minutes of drug administration.

 

SRC: NLM .