Marbofloxacin (Zeniquin®) for Dogs and Cats: Uses and Side Effects

Marbofloxacin (Zeniquin®) is an FDA-approved fluoroquinolone antibiotic used to treat a variety of bacterial infections in dogs and cats, particularly infections of the urinary tract, kidneys, prostate, skin, and soft tissues.

Here’s how marbofloxacin works, when it’s prescribed, possible side effects, dosing guidance, and important safety information.

What Is Marbofloxacin?

Marbofloxacin (generic for Zeniquin®) is an FDA-approved fluoroquinolone antibiotic used to treat a variety of bacterial infections in dogs and cats.

Common uses: Marbofloxacin is most commonly prescribed to treat bacterial infections affecting the:

• Bladder
• Kidneys
• Prostate
• Skin and soft tissues

Compounded marbofloxacin: In some cases, your veterinarian may recommend a compounded formulation when:

• Your pet has difficulty taking the commercially available formulation.
• The required dosage strength is not commercially available.
• Your pet is allergic to an ingredient in the FDA-approved medication.

Compounded medications are not FDA-approved. They are prepared by a veterinarian or licensed pharmacist to meet an individual patient's specific needs.

Safety Considerations for Marbofloxacin

Marbofloxacin is FDA-approved for use in dogs and cats, but veterinarians may also prescribe it extra-label for other species, including rabbits, reptiles, and birds, when appropriate.

Marbofloxacin should not be used in:

• Growing animals, because fluoroquinolone antibiotics can affect cartilage development
• Pregnant animals
• Pets with a known hypersensitivity to quinolone antibiotics
• Food-producing animals in the U.S.

Use marbofloxacin with caution in pets with known or suspected central nervous system disorders. Before starting treatment, tell your veterinarian about all of your pet's medications, vitamins, supplements, and medical conditions.

How Marbofloxacin Works

Marbofloxacin works by disrupting bacterial DNA replication, preventing susceptible bacteria from growing and multiplying.

How To Give Marbofloxacin

Give marbofloxacin exactly as directed by your veterinarian. It is typically given once daily and is best administered on an empty stomach.

Administration tips:

• Follow the directions on the prescription label or those provided by your veterinarian.
• If giving marbofloxacin on an empty stomach causes gastrointestinal upset, ask your veterinarian whether it can be given with a small amount of food.
• Avoid giving marbofloxacin with dairy products or supplements containing calcium, iron, or aluminum, as they can reduce the medication's absorption and effectiveness.
• If your pet vomits after receiving marbofloxacin, contact your veterinarian for guidance.
• Tell your veterinarian about all medications, vitamins, supplements, and herbal products your pet is taking before starting marbofloxacin, as some products can interfere with its absorption.

Missed a Dose?

If you miss a dose of marbofloxacin, contact your veterinarian for guidance. In many cases, they may recommend giving the missed dose when you remember. 

However, if it is almost time for your pet's next scheduled dose, they may advise skipping the missed dose and resuming the normal dosing schedule.

Do not give extra or double doses.

Marbofloxacin Side Effects

Marbofloxacin is generally well tolerated, but gastrointestinal upset and other side effects can occur.

Common side effects include:

• Vomiting
• Diarrhea
• Loss of appetite
• Lethargy
• Dehydration
• Skin rash

Rare but serious side effects may include:

• Lack of coordination
• Behavioral changes
• Shivering or shaking
• Liver irritation
• Depression
• Blindness
• Seizures

In cats, higher doses of marbofloxacin may cause blindness or other eye damage.

Marbofloxacin is not recommended for growing animals because fluoroquinolone antibiotics can interfere with normal cartilage development.

Fluoroquinolones, including marbofloxacin, may also increase sensitivity to sunlight. Avoid prolonged or direct sun exposure while your pet is taking this medication.

Human Side Effects

Marbofloxacin is not intended for human use.

When handling marbofloxacin:

• Avoid getting the medication in your eyes.
• Wash your hands thoroughly after administering the medication.
• If you are allergic to fluoroquinolone antibiotics, avoid handling this medication.
• Avoid prolonged sun exposure after handling marbofloxacin because skin sensitivity may occur.

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

Monitoring Your Pet

Your veterinarian may recommend monitoring or routine testing while your pet is taking marbofloxacin based on their individual health needs, other medications, and the condition being treated.

When To Call Your Veterinarian

Contact your veterinarian if:

• Your pet develops severe side effects.
• Your pet's condition worsens or does not improve with treatment.
• You suspect your pet has received an overdose.
• You have additional questions or concerns about using marbofloxacin.

Marbofloxacin Overdose

A marbofloxacin overdose can cause gastrointestinal upset and, in more severe cases, serious neurologic and systemic side effects. If you suspect an overdose, seek veterinary care immediately.

Common signs of an overdose include:

• Vomiting
• Diarrhea

Larger or prolonged overdoses may cause:

• Loss of appetite
• Dehydration
• Lethargy
• Tremors
• Facial swelling
• Red skin or ears
• Drooling
• Blindness

If you suspect your pet has received an overdose, contact your veterinarian immediately, seek emergency veterinary care, or contact an animal poison control center. Consultation fees may apply.

• Pet Poison Helpline: (855) 764-7661
• ASPCA Animal Poison Control: (888) 426-4435

How To Store Marbofloxacin

Store marbofloxacin according to the product label to help maintain its safety and effectiveness.

Storage instructions:

• Store marbofloxacin at controlled temperatures below 86 F (30 C).
• Always confirm storage instructions by reading the product label.
• Keep the container tightly closed to protect the medication from moisture and light.
• Store compounded formulations according to the instructions provided by the compounding pharmacy.
• Keep out of reach of children and pets.