Marbofloxacin: veterinary dose and monograph

At a glance

Drug class

Antibiotic

Also known as

Marbocyl, Marbomet, Forcyl, Zeniquin

Species with doses

Dogs, Cats, Cattle, Horses, Pigs and Reptiles

General dose range

2–8 mg/kg IM q24h — check the species tables for the indication

Routes

IM, PO

Last reviewed

1 October 2026

Indications

• Bovine respiratory disease (single-shot at 8 mg/kg or multi-day at 2 mg/kg)
• Acute & chronic mastitis (cattle / small ruminants)
• Metritis / endometritis
• Mastitis-Agalactia syndrome (pigs)
• Canine/feline UTI, pyoderma, soft tissue infections

Marbofloxacin dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

Dogs

• Susceptible UTI / soft tissue / pyoderma: Papich 5e and Plumb’s p.756 (Zeniquin label): 2.75–5.5 mg/kg PO once daily; skin/soft tissue for 2–3 days beyond resolution, UTI at least 10 days, maximum 30 days. Pseudomonas otitis: use the high end (5.5 mg/kg) (Cole 2008).

Cats

• Susceptible UTI / soft tissue: Papich 5e and Plumb’s p.756 (Zeniquin label): cats 2.75–5.5 mg/kg PO once daily; haemoplasmosis 2.75 mg/kg q24h (Dowers 2009); mycobacteria (not MAC) 2 mg/kg q24h (Gunn-Moore 2008).

Cattle

• Mastitis / metritis (multi-day): 1 mL / 50 kg b.wt. of 100 mg/mL. Papich 5e (calves): 2 mg/kg IV, SC or IM in the neck once daily for 3–5 days, or 8–10 mg/kg once IM.
• BRD — single shot: Papich 5e (calves): 8–10 mg/kg IM once, or 2 mg/kg once daily for 3–5 days. Withdrawals differ between single-shot and multi-day products and countries — follow the local label. Extra-label fluoroquinolone use in food animals is prohibited in some countries.

Horses

• Susceptible Gram-negative infection: Papich 5e: 2 mg/kg once daily IV or PO for susceptible Gram-negative bacteria; oral absorption is low, so 2 mg/kg PO may be insufficient for less susceptible organisms.

Goats

• No reference dose for this species: The previous 2–4 mg/kg IM goat row had no source; neither Papich 5e nor Plumb’s gives a small-ruminant marbofloxacin dose, and fluoroquinolone extra-label use in food animals is restricted.

Sheep

• No reference dose for this species: The previous 2–4 mg/kg IM sheep row had no source; neither Papich 5e nor Plumb’s gives a small-ruminant marbofloxacin dose, and fluoroquinolone extra-label use in food animals is restricted.

Pigs

• MMA syndrome / pneumonia: Papich 5e: pigs 2 mg/kg once daily IM (neck) for 3–5 days, or 8 mg/kg once. No withdrawal is given in Papich 5e or Plumb’s — follow the local product label.

Buffalo

No buffalo-specific doses are on file, so buffalo are dosed as cattle.

• Mastitis / metritis (multi-day): 1 mL / 50 kg b.wt. of 100 mg/mL. Papich 5e (calves): 2 mg/kg IV, SC or IM in the neck once daily for 3–5 days, or 8–10 mg/kg once IM.
• BRD — single shot: Papich 5e (calves): 8–10 mg/kg IM once, or 2 mg/kg once daily for 3–5 days. Withdrawals differ between single-shot and multi-day products and countries — follow the local label. Extra-label fluoroquinolone use in food animals is prohibited in some countries.

Reptiles

• Susceptible infection: Plumb's p.756 (Coke et al.): study in Ball pythons — 10 mg/kg PO at least every 48 hours. Further data needed on efficacy/toxicity across reptile species.

Contraindications

Hypersensitivity to fluoroquinolones. Young growing dogs (cartilage damage) — avoid in dogs <12–18 mo. Foals. Pregnancy / lactation (insufficient data). Severe renal failure (reduce dose).

Species-specific warnings

Cats: SAFER fluoroquinolone choice in cats than enrofloxacin — no hard retinal-toxicity cap. Still avoid >5.5 mg/kg/day.

Dogs: Standard dose 2.75–5.5 mg/kg PO q24h. AVOID in growing dogs (2–8 mo, small/medium breeds) — arthropathy.

Cattle: Multi-day mastitis dose: 2 mg/kg IM q24h × 3–5 d (6 d slaughter / 36 h milk). Single-shot BRD 8 mg/kg IM.

Horses: Foals: NEVER — fatal arthropathy. Adult horses: extra-label only.

Goats: 2–4 mg/kg IM q24h. Faster clearance than cattle.

Pigs: 2 mg/kg IM q24h × 3 days for MMA syndrome / pneumonia.

Adverse effects

• GI upset
• Cartilage abnormalities in juveniles
• CNS — rare seizures, ataxia (cautious use in epileptics)
• Local injection-site swelling

Drug interactions

• Aluminium / magnesium / calcium / iron antacids and sucralfate: chelate marbofloxacin — separate by 2 h
• Theophylline: marbofloxacin inhibits metabolism — risk of theophylline toxicity
• NSAIDs: may increase CNS excitation / seizure risk in seizure-prone animals
• Cyclosporine: increased nephrotoxicity
• Warfarin: may potentiate anticoagulation
• Probenecid: prolongs marbofloxacin half-life
• Phenobarbital: marbofloxacin inhibits its metabolism — INCREASED phenobarbital levels (caution in epileptic dogs)

Pregnancy and lactation

AVOID in pregnancy — arthropathy / cartilage damage in fetus (extrapolated from other fluoroquinolones). Excreted in milk. FDA Category D extrapolation. Use alternatives in pregnant breeding stock.

Monitoring

• Renal and hepatic function on prolonged courses
• Ocular examination in cats — safer than enrofloxacin but watch for vision change at high doses
• Joint examination in young growing dogs / foals
• Neurological status — especially in seizure-prone patients or with concurrent NSAIDs
• Withdrawal periods: cattle 6 d slaughter / 36 h milk (multi-day); single-shot may differ
• Phenobarbital levels if co-administered

Toxicity and overdose

Cats: SAFER than enrofloxacin for retinal toxicity — no hard dose cap at 5 mg/kg (still use caution at high doses). Dogs: cartilage erosion in growing dogs (2–8 mo, small/medium breeds) — same caveat as enrofloxacin. CNS: tremors, ataxia, seizures (especially in epileptic patients, with NSAIDs, or above-label dosing). Crystalluria at very high doses. SC injection: tissue irritation. Foals: severe arthropathy at therapeutic doses.

Management: No specific antidote. Discontinue. IV fluid diuresis, anti-seizure (diazepam 0.5 mg/kg IV prn), supportive care. Activated charcoal if recent ingestion. Monitor neurological and renal status.

Clinical pearls

• Cats: marbofloxacin is the PREFERRED fluoroquinolone — no hard 5 mg/kg cap like enrofloxacin (still avoid >5.5 mg/kg/day for safety)
• Dogs: 2.75–5.5 mg/kg PO q24h for skin / UTI / soft tissue
• Once-daily dosing exploits concentration-dependent killing
• BRD single-shot in cattle: 8 mg/kg IM — convenient but selects for resistance
• Pseudomonas otitis externa / cystitis: 5.5 mg/kg PO q24h
• Pregnant / growing animals: avoid (arthropathy)
• Marbomet 100 mg/mL is the Indian dairy standard for mastitis / metritis / BRD
• Concurrent phenobarbital: marbofloxacin INHIBITS phenobarbital metabolism — monitor pheno levels

Mechanism of action

Veterinary-only third-generation fluoroquinolone. Inhibits bacterial DNA gyrase (Gram-negative) and topoisomerase IV (Gram-positive) — disrupts DNA supercoiling, replication, and repair. Bactericidal, concentration-dependent killing with significant post-antibiotic effect. Broader spectrum than enrofloxacin against Gram-positives; comparable Gram-negative coverage including Pseudomonas. Excellent oral bioavailability (~95%) and tissue penetration. Once-daily dosing exploits concentration-dependent killing.

Formulations and products

• Marbomet injection 100 mg/mL (Intas, 30 mL)
• Marbocyl 2 % injection 20 mg/mL
• Marbocyl 10 % injection 100 mg/mL
• Marbomet (Intas (Neovet)) — 100 mg/mL, Injection

Storage

Tablets: 15–30 °C, dry. Injection: 15–25 °C, do NOT refrigerate (crystallisation). Multidose vial: discard 28 days after broaching.

Before you use this dose

Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

Other antibiotics

• Gentamicin
• Levofloxacin
• Lincomycin
• Linezolid
• Meropenem
• Minocycline
• Mupirocin
• Neomycin

Frequently asked questions