Active ingredient

Enrofloxacin for Animals: Mechanism, Doses by Species & Brands

Reviewed by Dr. Ravi Baraiya, B.V.Sc.Updated 2 Nov 20261 source

Enrofloxacin is a fluoroquinolone (DNA gyrase inhibitor) antibacterial ^[1]. The Baytril tablet label gives 5–20 mg/kg/day for dogs and a maximum of 5 mg/kg/day for cats ^[1].

Drug class: Fluoroquinolone antibacterial
Sourced doses for: Dogs, Cats
Brands on this site: Baytril, Fortivir

Enrofloxacin dose calculator

Type the strength printed on your own product. Results are calculated in your browser from the cited doses on this page — always check the label of the product you use.

Enrofloxacin dose by species

Species	Use	Dose	Route	How often	Basis
Dogs	Bacterial infections Total daily dose.	5–20 mg/kg^[1]	PO	Once daily or divided twice daily · 2–3 days beyond the end of clinical signs, maximum 30 days	Label
Cats	Bacterial infections Never more than 5 mg/kg per day in cats (retinal toxicity).	5 mg/kg^[1]	PO	Once daily or divided twice daily · 2–3 days beyond the end of clinical signs, maximum 30 days	Label

What enrofloxacin is used for

Dogs and cats: bacterial infections susceptible to enrofloxacin (Baytril tablets) ^[1].

How enrofloxacin works (mechanism of action)

Quinolone carboxylic acid derivatives are DNA gyrase inhibitors; in E. coli they inhibit DNA synthesis by preventing DNA supercoiling ^[1].

Safety, contraindications and precautions

Do not exceed 5 mg/kg per day in cats; rare retinal toxicity has been reported in cats ^[1].
Contraindicated in small and medium breeds of dogs during the rapid growth phase ^[1].
Contraindicated in animals hypersensitive to quinolones ^[1].

Brands that contain enrofloxacin

Brand	Company	Contains	Market
Baytril	Elanco	Enrofloxacin	USA (FDA label)
Fortivir	Virbac India	Enrofloxacin	India

Frequently asked questions

What is the enrofloxacin dose for cats?

5 mg/kg per day, never more, because of rare retinal toxicity ^[1].

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Medically reviewed by

Dr. Ravi Baraiya, B.V.Sc.

Veterinarian · Reviewed 2 Nov 2026

References

BAYTRIL (enrofloxacin) tablet, chewable — labelDailyMed (US NLM) — FDA-approved label, Elanco · 2026 · Product label
Passage read from this source
Tablets are available in three sizes (22.7, 68.0 and 136.0 mg enrofloxacin).
Administer orally at a rate to provide 5-20 mg/kg (2.27 to 9.07 mg/lb) of body weight.
Do not exceed 5 mg/kg of body weight per day in cats.
Quinolone carboxylic acid derivatives are classified as DNA gyrase inhibitors.

For veterinary professionals. Information supports — never replaces — clinical judgement; always check the current product label and local regulations.