Enrofloxacin dosing differs fundamentally between dogs and cats, and exceeding 5 mg/kg/day in cats carries a risk of irreversible retinal degeneration and blindness.
In dogs, enrofloxacin is administered orally at 5–20 mg/kg PO q24h (or divided q12h), with dose selection based on infection severity and pathogen susceptibility. Dogs receiving doses at the upper end of the range should be monitored closely for inappetence, depression, and vomiting.FDA DailyMed An… At 5 mg/kg/day in clinical field studies, only 2 of 270 dogs (0.7%) experienced drug-related side effects, both self-limiting vomition.FDA DailyMed An… Post-approval reporting has identified additional rare adverse effects in dogs including diarrhea, elevated liver enzymes, ataxia, seizures, depression, and lethargy.FDA DailyMed An…
In cats, the approved dose is strictly 5 mg/kg/day PO — administered either as a single daily dose or divided into two equal doses q12h — and this ceiling must not be exceeded. Treatment should continue at least 2–3 days beyond resolution of clinical signs, to a maximum of 30 days.FDA DailyMed An…+1 No drug-related side effects were reported in 124 cats treated at 5 mg/kg/day for 10 days in clinical field studies.FDA DailyMed An…
Retinal degeneration is the critical feline-specific toxicity and is dose-dependent. Post-approval reports in cats include mydriasis, retinal degeneration (manifesting as retinal atrophy, attenuated retinal vessels, and hyperreflective tapeta), and loss of vision.FDA DailyMed An… Mydriasis should be treated as a warning sign of impending or existing retinal changes.FDA DailyMed An… Acute diffuse retinal degeneration is a known dose-dependent adverse effect of enrofloxacin in cats.Journal of the… Additional feline adverse effects include vomiting, anorexia, elevated liver enzymes, diarrhea, ataxia, seizures, depression, lethargy, vocalization, and aggression.FDA DailyMed An…
In cats with reduced kidney function, no dose adjustment or interval prolongation is indicated based on pharmacokinetic data after intravenous administration. Clearance of enrofloxacin is similar among cats with normal and varying degrees of reduced renal function after a single dose, and reducing the dose or extending the interval could decrease concentrations needed for adequate bacterial eradication.Journal of Vete… The effects of cumulative dosing in azotemic cats have not yet been fully characterized.Journal of the…
Enrofloxacin is recommended as empiric therapy for pyelonephritis while urine culture results are pending, given favorable antibacterial activity against urinary tract pathogens, but therapy should be amended based on culture and susceptibility results.Journal of Vete… Restraint on fluoroquinolone use as initial therapy for all cases of acute kidney injury is warranted given increasing resistance among small animal uropathogens.Journal of the…
| Parameter | Dogs | Cats |
|---|---|---|
| Dose | 5–20 mg/kg PO q24h | 5 mg/kg/day PO (q24h or divided q12h) |
| Maximum dose | 20 mg/kg/day | 5 mg/kg/day — do not exceed |
| Max duration | 30 days | 30 days |
| Key adverse effects | Vomiting, anorexia, elevated liver enzymes, ataxia, seizures | Retinal degeneration/blindness (dose-dependent), vomiting, anorexia, seizures |
| Critical monitoring | Clinical signs at high doses | Mydriasis as early warning of retinal toxicity |
| Renal dose adjustment | Not addressed in sources | Not indicated Journal of Vete… |
Would you like guidance on pradofloxacin as an alternative fluoroquinolone in cats where higher dosing flexibility may be needed?