Dificid (Fidaxomicin) is a macrolide antibacterial agent used for the treatment of Clostridioides difficile-associated diarrhea (CDAD) in pediatric patients aged 6 months and older, as well as adult patients.

How to Use Dificid (Fidaxomicin)

Recommended Dosage Regimen

Adult patients: The recommended dose is 200mg (one tablet) taken orally twice daily (approximately every 12 hours) for 10 consecutive days. It can be taken with or without food.

Pediatric patients (6 months to under 18 years old):

Tablets: For patients with a body weight of ≥ 12.5kg who can swallow tablets, take 200mg (one tablet) orally twice daily for 10 consecutive days.

Oral suspension: For patients with a body weight of ≥ 4kg, the dosage is adjusted based on body weight (weight 4 - < 7kg: 80mg; 7 - < 9kg: 120mg; 9 - < 12.5kg: 160mg; ≥ 12.5kg: 200mg), taken twice daily for 10 consecutive days.

Administration Precautions

Tablets: Should be swallowed whole; do not chew, crush, or split.

Oral suspension: Must be shaken thoroughly before use, and an appropriate oral dosing device should be used to measure the accurate dose.

Management of missed dose: If a dose is missed by more than 6 hours, skip that dose and resume the regular dosing schedule at the next planned time.

Dificid (Fidaxomicin) Use in Special Populations

Hepatic Impairment

Mild impairment (Child-Pugh Class A): No dosage adjustment is required.

Moderate impairment (Child-Pugh Class B): Reduce the dose to 0.5mg per day.

Severe impairment (Child-Pugh Class C): Use is contraindicated.

Concomitant use with potent CYP1A2 inhibitors (e.g., ciprofloxacin): The dose should be reduced to 0.5mg per day.

Renal Impairment

Patients with mild to moderate renal impairment: No dosage adjustment is needed.

Patients with end-stage renal disease: Limited data are available on drug use, but no special dosage adjustment is required.

Pregnant and Lactating Women

Pregnant women: Available data are insufficient to assess the risk; use only when the potential benefit outweighs the risk.

Lactating women: No human data are available; a decision should be made based on weighing the pros and cons of continuing breastfeeding or discontinuing the drug.

Pediatric Use

6 months to under 18 years old: Efficacy has been established, and the dosage is adjusted based on body weight.

Under 6 months old: Efficacy has not been established.

Geriatric Use

No dosage adjustment is required for patients aged 65 years and older. However, monitoring has shown that plasma drug concentrations may be higher in elderly patients.