Vetdrugs 2.0Moxifloxacin is a fluoroquinolone antibacterial developed for human medicine and used extra-label in selected non-food-producing veterinary patients. Compared with several earlier fluoroquinolones, its spectrum includes greater activity against some gram-positive and anaerobic organisms. Veterinary systemic experience is limited, while ophthalmic preparations have a separate role in selected bacterial corneal infections.
Group
Fluoroquinolone antibacterial
Mechanism of Action
Moxifloxacin inhibits bacterial DNA gyrase and topoisomerase IV, stabilizing enzyme–DNA cleavage complexes and interrupting DNA replication and chromosome processing. Accumulation of DNA damage produces bactericidal activity. Its antibacterial effect is concentration dependent, with the useful spectrum determined by the organism and resistance mechanisms. Ophthalmic application produces local exposure at the ocular surface.
Dose Rates
Dogs
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Susceptible refractory infection | 10 mg/kg | PO | Every 24 h |
Cats
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Susceptible refractory infection | 10 mg/kg | PO | Every 24 h |
Indications
- Specialist extra-label treatment of selected susceptible refractory respiratory, skin or soft-tissue infections in companion animals, with limited clinical outcome evidence.
- Local treatment of selected susceptible bacterial keratitis or corneal ulcer infection with an ophthalmic formulation.
Contraindications
- Growing animals with cartilage-injury risk
- Avoid routine use in horses, rabbits and rodents because of enteritis risk.
- Use cautiously with seizure disorders or cardiac repolarization abnormalities.
Interactions
- Oral metal cations can reduce absorption.
- Do not mix with metal-ion-containing products; other QT-prolonging drugs may increase cardiac risk.
Adverse effects
- Vomiting, diarrhoea and central nervous system effects
- Juvenile arthropathy
- Dose-related QT prolongation
Toxicity
Stop treatment for neurologic, severe gastrointestinal or cardiac reactions; assess ECG and electrolyte status when indicated.
Preparations
| Preparation | Form | Strength | Route |
|---|---|---|---|
| Moxifloxacin 400 mg tablet | Tablet | 400 mg / tablet | PO |
| Moxifloxacin 1.6 mg/mL injection | Injection | 1.6 mg / mL | IV |
| Vigamox moxifloxacin 5 mg/mL ophthalmic drops Sterile ophthalmic preparation only; no systemic use. Drop-volume dosing is not a mass-based prescription. | Other | 5 mg / mL | TOPICAL |
Monitoring and Administration
Use susceptibility testing and assess alternatives with better established veterinary data.
The described equine regimen caused diarrhoea; route is not specified in its dosage entry and is not inferred.
Avoid food-animal administration; the no established withdrawal period.
Historical equine study exposure: 5.8 mg/kg every 24 hours for 3 days. Diarrhoea occurred; the incomplete route and gastrointestinal risk prevent an enabled equine regimen.
Topical ocular fluoroquinolones can cause irritation or hypersensitivity. The provided appendix establishes a 5 mg/mL moxifloxacin eye-drop preparation but does not give a drug-specific dosing interval; no drop frequency is invented.