Dificid (Fidaxomicin) is a macrolide antibiotic specifically indicated for the treatment of diarrhea caused by Clostridioides difficile (CDAD).
What are the Side Effects of Dificid (Fidaxomicin)?
Common Side Effects in Adult Patients
Gastrointestinal reactions: Nausea (11%), vomiting (7%), abdominal pain (6%), gastrointestinal bleeding (4%)
Hematological abnormalities: Anemia (2%), neutropenia (2%)
Others: Thrombocytopenia, elevated liver enzymes, metabolic acidosis (incidence < 2%)
Common Side Effects in Pediatric Patients
Gastrointestinal reactions: Abdominal pain (8.2%), vomiting (7.1%), diarrhea (7.1%), constipation (5.1%)
Systemic symptoms: Fever (13.3%)
Cutaneous reactions: Rash (5.1%)
Liver function abnormalities: Elevated transaminases (5.1%)
Serious Side Effects of Dificid (Fidaxomicin) Requiring Vigilance
Allergic Reactions
Fidaxomicin may trigger acute allergic reactions.
Angioedema (swelling of the mouth, throat, and face)
Dyspnea (difficulty breathing), pruritus (itching), rash
In severe cases, discontinue the drug immediately and seek medical attention.
Risk of Intestinal Microbiota Imbalance
Fidaxomicin is only effective against Clostridioides difficile. Its misuse may increase the resistance of other bacteria.
Precautions for Administration of Dificid (Fidaxomicin)
Dosage and Administration
Adults: 200mg tablets, twice daily, for 10 consecutive days (may be taken with or without food).
Pediatric patients:
Patients ≥ 12.5kg who can swallow tablets: 200mg tablets, twice daily.
Patients < 12.5kg or unable to swallow tablets: Adjust the dose of oral suspension based on body weight (see the weight-based dosage table in the drug package insert).
Drug Interactions
Cyclosporine: May increase the blood concentration of fidaxomicin, but the clinical significance is unclear; no dose adjustment is required.
P-gp inhibitors: No dose adjustment is required.
Special Storage Requirements
Oral suspension: After reconstitution, store under refrigeration (2°C - 8°C) and use within 12 days.
Tablets: Store at room temperature and protect from moisture.
Patient Education
Complete the full course of treatment: Even if symptoms improve, complete the 10-day treatment course to prevent recurrence.
Recognize allergic symptoms: If symptoms such as rash or difficulty breathing occur, seek medical attention immediately.
Avoid misuse: Use only for confirmed or highly suspected Clostridioides difficile infections.


