Drug side effects
fidaxomicin Side Effects
The reactions most often reported to the FDA for fidaxomicin (also sold as Dificid), with demographics, serious outcomes, and reporting trends.
Data updated 2026-05-15
- 2,273
- FAERS reports
Data from the FDA Adverse Event Reporting System (FAERS), 2011 to 2025. A FAERS report records a temporal association, not proof of cause. See our methodology for how figures are compiled and de-duplicated.
The most commonly reported side effects of fidaxomicin come from 2,273 reports to the FDA, broken down here by frequency, patient demographics, and serious outcomes.
This page analyzes 2,273 reports to the FDA Adverse Event Reporting System (FAERS) for fidaxomicin (Dificid): the reactions reported most often, who reported them, serious outcomes such as hospitalization, and year-over-year trends. A FAERS report does not prove the drug caused the effect, and report volume tracks how widely a drug is used, not how likely an effect is for any one person. Educational information, not medical advice.
Total Reports
2,273
Reports Mentioning Death
248
10.9% of reports — not proof the medicine caused the death
Hospitalizations
699
30.8% of reports
Top Indication
Clostridium Difficile Infection
Most Reported Adverse Reactions
Who Reports Side Effects
Gender Distribution
Age Distribution
Reporting Trend by Year
Reactions in Death Reports
Top reactions reported in 248 reports where death was an outcome. These are voluntarily reported and do not establish causation.
| Reaction | Reports |
|---|---|
| DEATH | 69 |
| CLOSTRIDIUM DIFFICILE INFECTION | 45 |
| DIARRHOEA | 29 |
| SEPTIC SHOCK | 28 |
| SEPSIS | 25 |
| RESPIRATORY FAILURE | 24 |
| DYSPNOEA | 20 |
| ANAEMIA | 18 |
| CLOSTRIDIUM DIFFICILE COLITIS | 18 |
| HYPOXIA | 18 |
| MELAENA | 18 |
| PYREXIA | 18 |
| MALAISE | 17 |
| CHEST PAIN | 16 |
| CHILLS | 16 |
| GASTROENTERITIS | 16 |
| PATHOGEN RESISTANCE | 16 |
| DRUG RESISTANCE | 14 |
Reactions in Hospitalization Reports
Top reactions in 699 reports where hospitalization was an outcome.
| Reaction | Reports |
|---|---|
| CLOSTRIDIUM DIFFICILE INFECTION | 191 |
| DIARRHOEA | 123 |
| CLOSTRIDIUM DIFFICILE COLITIS | 82 |
| PYREXIA | 55 |
| NAUSEA | 53 |
| DISEASE RECURRENCE | 51 |
| ACUTE KIDNEY INJURY | 41 |
| VOMITING | 37 |
| SEPSIS | 36 |
| SEPTIC SHOCK | 34 |
| ANAEMIA | 33 |
| DYSPNOEA | 33 |
| RESPIRATORY FAILURE | 33 |
| ABDOMINAL PAIN | 31 |
| MALAISE | 30 |
| FATIGUE | 28 |
| CLOSTRIDIUM TEST POSITIVE | 27 |
| PANCYTOPENIA | 24 |
Nearby, Related Medications
What the FAERS Data Reveals About fidaxomicin Side Effects
The FDA Adverse Event Reporting System (FAERS) contains 2,273 voluntary reports linked to fidaxomicin and its brand equivalents (Dificid), spanning 2011 through 2025. Of those, 248 (10.9%) listed death as an outcome and 699 (30.8%) involved hospitalization. The most common indication reported alongside adverse events was Clostridium Difficile Infection.
Demographic breakdowns help contextualize who is being exposed to the drug. Of reports with known sex, 60% were female and 36% male; age distribution skews toward 75+, with 422 reports in that bracket. The single most reported reaction is clostridium difficile infection with 461 submissions, followed by diarrhoea and disease recurrence.
How to read these numbers
FAERS is a signal-detection tool, not a scorecard. Reports are voluntary, and a single case may list multiple suspect drugs, so numbers above should not be read as incidence rates or per-patient risk. Widely prescribed drugs naturally accumulate more reports than niche therapies even when individual risk is low. These aggregates are useful for spotting patterns that merit further pharmacovigilance, not for choosing between medications. This page is for educational reference only and is not medical advice, speak with a licensed clinician about any side-effect concerns.
Drugs With a Similar FAERS Report Volume
Other medications with a total FDA adverse-event report count closest to fidaxomicin's 2,273.
Read our methodology - how this data is sourced, computed, and verified.