Enrofloxacin (Baytril®) for Dogs and Cats

Stephanie Howe, DVM
By Stephanie Howe, DVM. Reviewed by Molly Price, DVM on Mar. 28, 2024
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PetMD’s medications content was written and reviewed by veterinary professionals to answer your most common questions about how medications function, their side effects, and what species they are prescribed for. This content shouldn’t take the place of advice by your vet.

What Is Enrofloxacin for Dogs and Cats?

Enrofloxacin is an antibiotic in a class called fluoroquinolones, which treat a wide variety of bacteria. It is FDA-approved for use in dogs and cats to manage bacterial infections that are susceptible to enrofloxacin, such as certain respiratory, urinary tract, and skin infections. Baytril® is the brand name for a veterinary prescription antibiotic called enrofloxacin.

The oral tablet formulation of Baytril® (film coated and flavored tablet) is FDA-approved for use in both dogs and cats, while the injectable version (administered by a trained veterinary professional) and ear suspension (Baytril® Otic) are approved for use in dogs only.

However, Baytril® is readily utilized in the veterinary field across many different species, such as non-food producing cattle, horses, small mammals, reptiles, and birds for off-label uses.  The term off- or extra-label means that a medication is used in a way or in a particular species that is not specified on the medication label. While veterinarians often prescribe medications for off-label uses, your veterinarian will determine whether Baytril® is right for your pet.  

In certain circumstances, your vet may recommend a compounded formulation of enrofloxacin. Compounded medications are prescribed if there’s a specific reason your pet’s health can’t be managed by an FDA-approved drug, such as if your pet has trouble taking pills in capsule form, the dosage strength is not commercially available, or the pet is allergic to an ingredient in the FDA-approved medication.

Compounded medications are not FDA-approved. They are created by either a veterinarian or a licensed pharmacist on an individual basis to best suit a patient’s particular needs. You can learn more about compounded medications here. Your veterinarian will determine whether a compounded medication is right for your pet.

Enrofloxacin Considerations

It is important to note that Baytril® is not recommended for use in dogs during the rapid growth phase (between 2 and 8 months of age). Baytril® and other antibiotics of the fluoroquinolone class can cause abnormal cartilage development in growing animals. Speak with your veterinarian about whether your pet is still in its growth stage.

Safety studies have shown Baytril® is safe in breeding, pregnant, and nursing dogs, but because of the risk for cartilage abnormalities in growing animals, veterinarians generally do not recommend the product for use during your pet’s pregnancy or lactation.

Baytril® should not be used in pets who are hypersensitive to it. It should be used with caution in pets with neurological disorders. Giving Baytril® with certain medications can result in health risks to your pet, so it is important to discuss your pet’s medications, including vitamins and supplements, and medical conditions with your veterinarian.

How Enrofloxacin Works in Dogs and Cats

Fluoroquinolone antibiotics work by blocking the bacteria’s DNA replication, which prevents the bacteria from multiplying.

Enrofloxacin Directions for Dogs and Cats

Follow the directions on the drug label or as provided by your veterinarian. This oral medication is best absorbed if given on an empty stomach and is generally given once daily. If giving this medication on an empty stomach causes stomach upset, then giving it with a small amount of food is an option.

Animals on this medication should have consistent access to water. It is important to speak with your veterinarian about the proper way to administer this medication to your pet. Contact your veterinarian if your animal vomits while on this medication.

Missed a Dose?

Speak with your veterinarian about what to do if you forget to give a dose of enrofloxacin Your veterinarian may recommend that you give it when you remember, or, if it is almost time for your next dose, to skip the missed dose and resume your normal dosing schedule. Speak with your veterinarian regarding specific dosing instructions for your pet. Do not give extra or double doses.

Enrofloxacin Possible Side Effects in Dogs and Cats

Baytril® and enrofloxacin may cause gastrointestinal side effects, including: 

  • Vomiting
  • Diarrhea
  • Lack of appetite
  • Abdominal pain

Rarely, the following severe side effects may occur:

  • Wobbliness, loss of balance
  • Liver irritation and elevated liver levels
  • Depression
  • Lethargy
  • Seizures
  • Nervousness
  • Aggression
  • Vocalization

When used at higher doses in cats, this medication can negatively affect the eyes, causing dilated (larger) pupils, retinal degeneration, or blindness. If you notice your cat’s pupils are larger than usual while on this medication, immediately contact your veterinarian or seek emergency veterinary care.

This medication is not recommended for use in growing animals of any species. Baytril® and other antibiotics of the fluoroquinolone class can cause abnormal cartilage development in growing animals. Speak with your veterinarian regarding risks associated with growing animals before administering this medication.

Baytril® and other medications in the fluoroquinolone class can cause increased sensitivity to sunlight. Direct or prolonged sun exposure should be avoided when on this medication.

Human Side Effects

Baytril® is a prescription veterinary medication not intended for use in humans.

Due to possible side effects, humans should never use medicine dispensed for their pets and pets should not be given any medicine dispensed for a human’s use.

If you are allergic to Baytril® or other fluoroquinolone antibiotics, talk to your veterinarian about using another medication or ensure that you wear gloves at all times while in contact with this medication.

Avoid contact with eyes, and in case of contact immediately flush eyes with copious amounts of water for 15 minutes. In case of skin contact, wash skin with soap and water and avoid direct sunlight. Consult a physician if eye or skin irritation persists.

If you accidentally ingest a pet medication, call your physician or the national Poison Control Center hotline at 800-222-1222.   

Call Your Vet If:

  • Severe side effects are seen (see above)
  • Your pet’s condition worsens or does not improve with treatment.
  • You see or suspect an overdose
  • You have additional questions or concerns about the use of Baytril® (enrofloxacin)

Enrofloxacin Overdose Information in Dogs and Cats

The severity of an enrofloxacin overdose depends on the species and the amount given by weight.

In dogs, the most common symptoms are vomiting, loss of appetite, lethargy, and loss of coordination.

In cats, overdoses may cause serious effects to the nervous system such as seizures or blindness.

If you suspect an overdose, immediately contact your veterinarian, seek emergency veterinary care, or call an animal poison control center. Consultation fees often apply.

Pet Poison Helpline (855) 764-7661

ASPCA Animal Poison Control (888) 426-4435

Enrofloxacin Storage for Dogs and Cats

Always confirm storage requirements by reading the prescription label.

Baytril® should be stored at or below 77 F.

Keep the container tightly closed to protect the medicine from moisture and light.

Compounded medications should be stored according to the compounding pharmacy’s label.

Keep out of reach of children and pets.


What is Baytril® used for in dogs?

Baytril® is an FDA-approved antibiotic for dogs used to treat certain susceptible bacterial infections of the respiratory system, urinary tract, and skin.

How fast does Baytril® work in pets?

Baytril® can begin working within two hours of your pet taking it, but it may take up to several days for your pet to feel better, depending on their underlying medical condition and individual health status.

Is Baytril® safe for rabbits?

Yes, Baytril® can be used safely, under a veterinarian’s direct supervision, for certain susceptible bacterial infections in rabbits. It’s important to understand that there are no antibiotics approved by the FDA for rabbits. Speak with your vet first to ensure this medication is appropriate for your rabbit.

No vet writer or qualified reviewer has received any compensation from the manufacturer of the medication as part of creating this article. All content contained in this article is sourced from public sources or the manufacturer.


Stephanie Howe, DVM


Stephanie Howe, DVM


Dr. Stephanie Howe graduated from the University of Florida College of Veterinary Medicine in 2011, after receiving a Bachelor of Science...

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