Ciprofloxacin: veterinary dose and monograph

At a glance

Drug class

Antibiotic

Also known as

Cipro, Ciplox, Cifran, Ciprobid, Zoxan

Species with doses

Dogs, Cats, Birds, Rabbits, Ferrets, Guinea pigs, Reptiles, Chinchillas, Hamsters, Rats, Mice, Gerbils, Hedgehogs, Sugar gliders and Primates

General dose range

10–20 mg/kg PO q24h — check the species tables for the indication

Routes

PO, IV

Last reviewed

1 October 2026

Indications

• Susceptible Gram-negative infections (E. coli, Klebsiella, Proteus, Pseudomonas)
• Complicated / resistant urinary tract infection
• Skin and soft-tissue infection, pyoderma
• Prostatitis (good tissue penetration)
• Respiratory infection with susceptible organisms
• Bacterial keratitis / conjunctivitis (ophthalmic)

Ciprofloxacin 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 systemic infection: Plumb’s p.276 (Greene 2006): skin/soft tissue 10–15 mg/kg PO q24h; bone, systemic, bacteraemia or resistant pathogens 20 mg/kg PO q24h, 7–14 days; 5–15 mg/kg PO q12h (Vaden & Papich). Papich 5e: 25 mg/kg q24h PO — oral absorption in dogs is low and variable. Avoid in growing dogs.
• UTI: Plumb’s p.276 (Greene 2006): UTI 10 mg/kg PO once daily for 7–14 days.
• Severe infection (IV): Papich 5e: 15 mg/kg q24h IV. Infuse over 30–60 min.

Cats

• Susceptible infection: Plumb’s p.276 (Vaden & Papich 1995): 5–15 mg/kg PO q12h. Papich 5e: 20 mg/kg q24h PO or 10 mg/kg q24h IV. Avoid in young, pregnant or breeding animals; reduce in renal failure.

Cattle

• Not recommended (food animal): Neither Papich 5e nor Plumb’s gives a ciprofloxacin dose for cattle. Use an approved veterinary fluoroquinolone only where the local label and law allow.

Buffalo

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

• Not recommended (food animal): Neither Papich 5e nor Plumb’s gives a ciprofloxacin dose for cattle. Use an approved veterinary fluoroquinolone only where the local label and law allow.

Birds

• Susceptible infection: Plumb’s p.276: crushed tablets 20 mg/kg PO q12h (Bauck & Hoefer 1993); 10–15 mg/kg PO q12h (Hoeffer 1995); up to 20–40 mg/kg PO twice daily (McDonald 1989). Ratites 3–6 mg/kg PO twice daily.

Rabbits

• Susceptible infection: Plumb’s p.276: rabbits 5–20 mg/kg PO q12h (Ivey & Morrisey 2000); pasteurellosis 15–20 mg/kg PO twice daily for at least 14 days, months in chronic cases (Antinoff 2008).

Ferrets

• Susceptible infection: Plumb’s p.276 (Williams 2000): ferrets 5–15 mg/kg PO twice daily.

Guinea pigs

• Susceptible infection: Plumb’s p.276 (Adamcak & Otten 2000): chinchillas, gerbils, guinea pigs, hamsters, mice and rats 7–20 mg/kg PO q12h.

Reptiles

• Susceptible infection: Carpenter’s Exotic Animal Formulary (reptile antimicrobial table): most species 10 mg/kg PO q48h; reticulated pythons 11 mg/kg PO q48–72h. Plumb’s gives no reptile ciprofloxacin dose. (The previous 4 mg/kg q8–12h figure was not supported.)

Chinchillas

• Susceptible infection: Plumb’s p.276 (Adamcak & Otten 2000): 7–20 mg/kg PO q12h.

Hamsters

• Susceptible infection: Plumb’s p.276 (Adamcak & Otten 2000): 7–20 mg/kg PO q12h.

Rats

• Susceptible infection: Plumb’s p.276 (Adamcak & Otten 2000): 7–20 mg/kg PO q12h.

Mice

• Susceptible infection: Plumb’s p.276 (Adamcak & Otten 2000): 7–20 mg/kg PO q12h.

Gerbils

• Susceptible infection: Plumb’s p.276 (Adamcak & Otten 2000): 7–20 mg/kg PO q12h.

Hedgehogs

• Susceptible infection: Carpenter Exotic Animal Formulary 6th ed, Table 8-1 (p.512): hedgehogs 5–20 mg/kg PO q12h.

Sugar gliders

• Susceptible infection: Carpenter Exotic Animal Formulary 6th ed, Table 7-1 (p.497): sugar gliders 10 mg/kg PO q12h.

Primates

• Susceptible infection (monkeys, marmosets): Carpenter Exotic Animal Formulary 6th ed, Table 13-1 (p.681): monkeys 10 mg/kg PO q12h; marmosets/chimpanzees 10–20 mg/kg PO q12h.

Contraindications

Growing animals — arthropathy/cartilage erosion in juvenile large-breed dogs (<8 months) and young horses. Avoid in patients with seizure disorders (GABA antagonism lowers threshold). Do NOT exceed 5 mg/kg/day in cats (enrofloxacin-class retinal toxicity, though ciprofloxacin is lower-risk). Known fluoroquinolone hypersensitivity.

Species-specific warnings

Cats: Dose-dependent acute retinal degeneration and permanent blindness above ~5 mg/kg/day. Keep doses low and watch for dilated pupils / vision loss.

Dogs: Do not use in growing large/giant-breed dogs (<8 months) — irreversible articular cartilage damage.

Horses: Avoid in foals — arthropathy. Oral absorption in adult horses is poor and it can disturb hindgut flora.

Adverse effects

• GI: vomiting, anorexia, diarrhoea
• CNS: seizures (especially with NSAIDs or in epileptics), ataxia
• Cartilage damage in growing animals
• Retinal degeneration / blindness in cats at high doses
• Crystalluria in alkaline urine
• Rare hepatotoxicity, QT prolongation

Drug interactions

• Di-/tri-valent cations (antacids, sucralfate, dairy, iron, calcium, magnesium, zinc): chelation drastically reduces oral absorption — separate by ≥2 h
• Theophylline / methylxanthines: inhibits clearance → theophylline toxicity (seizures, arrhythmia)
• NSAIDs: additive CNS excitation, increased seizure risk
• Warfarin: potentiates anticoagulation
• Cyclosporine: increased nephrotoxicity
• Sucralfate / oral phosphate binders: markedly reduce bioavailability

Pregnancy and lactation

Avoid in pregnancy where alternatives exist — arthropathy risk to developing cartilage of the fetus and crosses into milk. Use only if benefit outweighs risk.

Monitoring

• Renal function (BUN/creatinine) on prolonged or high-dose therapy
• CNS signs — discontinue if tremor/seizure
• Feline vision / pupillary responses on any course
• Culture & sensitivity — preserve fluoroquinolones for confirmed susceptibility (stewardship)
• Clinical response at 48–72 h

Toxicity and overdose

Acute overdose: CNS stimulation (tremor, seizures), GI upset, crystalluria, acute kidney injury. Cats are uniquely susceptible to retinal degeneration (acute blindness, mydriasis) at doses >5 mg/kg/day — a fluoroquinolone class effect. Cartilage toxicity in juveniles.

Management: No specific antidote. Decontaminate if recent oral ingestion (emesis/charcoal). IV fluids to force diuresis and prevent crystalluria; keep urine output high. Control seizures with diazepam/midazolam then phenobarbital. Monitor renal values and, in cats, perform fundic exam.

Clinical pearls

• In dogs, enrofloxacin (which is de-ethylated to ciprofloxacin in vivo) gives more reliable plasma levels — prefer it unless using cheap human ciprofloxacin for cost reasons
• Concentration-dependent killing: give the full daily dose ONCE daily rather than split, to maximise Cmax/MIC
• Never co-administer with antacids, sucralfate, or on a full dairy meal — chelation can abolish absorption
• Reserve for culture-confirmed resistant Gram-negatives; empiric overuse drives fluoroquinolone resistance
• Cats: hard ceiling of 5 mg/kg/day — irreversible blindness has occurred above this

Mechanism of action

Inhibits bacterial DNA gyrase (topoisomerase II) and topoisomerase IV, blocking DNA supercoiling, replication and transcription — rapid, concentration-dependent bactericidal killing with a post-antibiotic effect. Efficacy tracks Cmax/MIC and AUC/MIC ratios, favouring high once-daily dosing.

Formulations and products

• 250 mg tablet
• 500 mg tablet
• IV infusion 2 mg/mL (100 mL bag)
• Ophthalmic solution 3 mg/mL (0.3%)
• Zenflox Vet (Various (India)) — Ciprofloxacin 100 mg/mL, Injection / oral
• Ciprovet eye drops (Various) — 0.3 % (3 mg/mL), Ophthalmic solution
• Ciplox — 250 / 500 mg tablet; 0.3 % eye/ear drops; 2 mg/mL IV, Tablet / drops / IV (human-label)
• Cifran — 250 / 500 / 750 mg tablet, Tablet (human-label)
• Ciprobid — 250 / 500 mg tablet, Tablet (human-label)

Storage

Tablets: 15–30 °C, protect from light/moisture. IV bags: room temperature, protect from light; do not refrigerate (precipitation). Ophthalmic: 2–25 °C, discard 4 weeks after opening.

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

• Ceftriaxone
• Cefuroxime
• Cephalexin
• Chloramphenicol
• Clarithromycin
• Clindamycin
• Cloxacillin
• Colistin (Polymyxin E)

Frequently asked questions