Fusidic acid
Also known as: Betafuse · Canaural · Isaderm · Isathal · Trigoderm · Sodium fusidate
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Dosing by species
Dosing data for this drug is not yet available in the VetSheet formulary. Every other section below is complete. Consult the current product label before prescribing.
Overview
Fusidic acid is a topical antibiotic primarily active against Gram-positive bacteria, particularly Staphylococcus pseudintermedius. It is utilized topically in the management of staphylococcal infections of the conjunctiva, skin, or ear. It is notable for its ability to penetrate intact skin and the cornea, gaining access to the anterior chamber of the eye.
Clinical Pearl: The carbomer gel vehicle in the ocular preparation (e.g., Isathal) may also be efficacious as a surface lubricant for the eye.
Mechanism of action
Fusidic acid works by inhibiting bacterial protein synthesis. It binds to the bacterial elongation factor G (EF-G) on the ribosome → prevents the translocation of the growing peptide chain → halts bacterial growth.
Safety & warnings
Contraindications
- Do not use preparations containing corticosteroids in pregnant animals
Adverse effects
- No specific adverse reactions reported in the monograph
Precautions
Avoid contamination of the container on application.
Warning: Do not use combination preparations containing corticosteroids in pregnant animals.
Monitoring
- Resolution of clinical signs of infection (skin, ear, or eye)
Pharmacokinetics
Absorption
Able to penetrate skin and penetrate the cornea gaining access to the anterior chamber of the eye.
Overdose
No information available.
Available products
Formulations
- 5 mg/g fusidate suspension
- 0.5% fusidic acid + 0.1% betamethasone gel
- 1% fusidic acid viscous solution
Veterinary
- Betafuse
- Canaural (contains framycetin, nystatin, prednisolone)
- Isaderm (contains betamethasone)
- Isathal
- Trigoderm (contains betamethasone)
Regulatory status
Available as POM-V
Available as POM-V
No regulatory data for: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Keep container tightly closed to avoid contamination.
Client information
Administration: Apply the medication exactly as directed by your veterinarian.
Hygiene: Avoid touching the tip of the tube or bottle to the eye, ear, or skin to prevent contamination of the container.
Pregnancy Warning: If your pet is pregnant, inform your veterinarian, as some fusidic acid products contain steroids which should not be used during pregnancy.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.