fidaxomicin at a glance
Medicine class
Macrocyclic antibacterial
Main use
Clostridioides difficile infection affecting the bowel
Where it acts
Mainly within the gut, with very limited absorption into the bloodstream
Food
Tablets and oral suspension may be taken with or without food
Available forms
Film-coated tablets and granules prepared as an oral suspension
What is fidaxomicin used for?
Licensed uses include:
Clostridioides difficile infection in adults.
Clostridioides difficile infection in children and adolescents; formulation choice depends on age, weight and ability to swallow.
How does fidaxomicin work?
Fidaxomicin blocks bacterial RNA polymerase, preventing C. difficile from making RNA needed for survival. It kills the bacteria, has a narrow antibacterial spectrum and acts predominantly in the bowel. Laboratory studies also show inhibition of C. difficile spore formation.
fidaxomicin preparations and strengths
Oral suspension
Route: Oral
Strengths: 40 mg/mL
Tablet
Route: Oral
Strengths: 200 mg
How to take fidaxomicin
Follow the dispensing label and instructions from your prescriber or pharmacist.
Swallow tablets whole with water.
Take either formulation with or without food.
A pharmacist or other healthcare professional must prepare the oral suspension; patients and carers should not reconstitute it at home.
Before giving the suspension, remove it from the refrigerator briefly and shake it gently as instructed. Measure it only with the supplied oral syringe and adaptor, then return it to the refrigerator.
The oral suspension can be given through a compatible enteral feeding tube. Follow the appropriate tube and flushing instructions.
fidaxomicin side effects
Common or expected effects
- Nausea
- Vomiting
- Constipation
Get urgent medical advice
- Difficulty breathing or swelling of the face or throat, which may indicate a severe allergic reaction
- Severe rash, severe itching or widespread hives
fidaxomicin in pregnancy
There are no adequate human pregnancy data. Although animal studies did not indicate reproductive harm and absorption into the bloodstream is low, product information advises avoiding fidaxomicin during pregnancy as a precaution unless the prescriber considers treatment appropriate.
fidaxomicin while breastfeeding
It is unknown whether fidaxomicin or its metabolites enter human milk. Low maternal absorption suggests infant exposure is likely to be small, but risk cannot be excluded. Review the benefits of treatment and breastfeeding with the prescriber.
fidaxomicin interactions
Clinically relevant interactions mainly involve the P-glycoprotein transporter.
Potent P-glycoprotein inhibitors, including ciclosporin, ketoconazole, erythromycin, clarithromycin, verapamil, dronedarone and amiodarone
These can increase exposure to fidaxomicin and its active metabolite. Combined use is not recommended unless specifically reviewed by the prescriber.
Dabigatran etexilate
Fidaxomicin may increase intestinal absorption of this anticoagulant, so the combination requires clinical review.
Common questions about fidaxomicin
Answers are fully visible for fast scanning and source review.
Can fidaxomicin be taken with food?
Yes. Both tablets and oral suspension can be taken with or without food.
Can fidaxomicin tablets be crushed?
Crushing tablets is off-label. A licensed oral suspension is available, so formulation choice should be discussed with pharmacy and, where relevant, the swallowing team.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.