Home/Medicines/Phenylbutazone

Phenylbutazone

Prescription

NSAID (Pyrazolone)

Last reviewed 21 Apr 2026 · PetCare.AI Editorial Team

Species

Dog, Cat

Brands

1 available

Interactions

1 documented

Formulations

Mechanism of action

Non-selective COX-1 and COX-2 inhibitor with potent anti-inflammatory, analgesic, and antipyretic properties. One of the most potent veterinary NSAIDs but with significant toxicity concerns — primarily used in horses; limited use in dogs.

At a glance

Class

NSAID (Pyrazolone)

Schedule

Prescription

Storage

Store at room temperature, protect from light

Dosing

🐕

Dog

VERY narrow safety margin in dogs — severe GI ulceration and bone marrow suppres

Dose

3–7 mg/kg

Route

Frequency

q8h initially then reduce

🐈

Cat

NEVER use in cats

Dose

—

Route

N, A

Frequency

N/A

Educational reference only

This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet. Find a vet near you →

Formulations

💊

Other — 3

Strength

—

Strength

—

Strength

—

Storage

Store at room temperature, protect from light

Safety

Monitoring parameters

CBC every 3–5 days during useGI signs (melena, vomiting)Hepatic and renal functionLimit duration

Educational reference only

Interactions

Contraindicated — 1

Prednisolone

contraindicated

Phenylbutazone (highest GI toxicity of all NSAIDs) + corticosteroid: extremely high risk of fatal GI perforation.

Management: NEVER combine. Phenylbutazone already has a very narrow safety margin — adding steroid is extremely dangerous.

Educational reference only

Brands

Other markets

Butazolidin

FAQs

Frequently asked questions

›What is Phenylbutazone?

Phenylbutazone is a nsaid (pyrazolone) used in pets. Non-selective COX-1 and COX-2 inhibitor with potent anti-inflammatory, analgesic, and antipyretic properties. One of the most potent veterinary NSAIDs but with significant toxicity concerns — primarily used in horses; limited use in dogs.

›What is Phenylbutazone used for in pets?

Phenylbutazone is used in veterinary medicine for: VERY narrow safety margin in dogs — severe GI ulceration and bone marrow suppres; NEVER use in cats.

›What is the Phenylbutazone dose for dogs?

For dogs, Phenylbutazone is typically dosed as follows — VERY narrow safety margin in dogs — severe GI ulceration and bone marrow suppres: 3–7 mg/kg PO q8h initially then reduce. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.

›What is the Phenylbutazone dose for cats?

For cats, Phenylbutazone is typically dosed as follows — NEVER use in cats: undefined undefined N/A N/A. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.

›Does Phenylbutazone need a prescription?

Yes. Phenylbutazone is a prescription medication and should only be administered under veterinary supervision.

Educational reference only