Animal NDC 58005-825-04 Phenylbutazone

Animal Product Information

Field Name Field Value
Animal NDC Code 58005-825-04
Proprietary Name Phenylbutazone What is the Proprietary Name?
The proprietary name also known as the trade name is the name of the product chosen by the medication labeler for marketing purposes.
Non-Proprietary Name Phenylbutazone What is the Non-Proprietary Name?
The non-proprietary name is sometimes called the generic name. The generic name usually includes the active ingredient(s) of the product.
Labeler Name Sparhawk Laboratories, Inc.
Product Type Prescription Animal Drug
Usage Information
        For relief of inflammatory conditions associated with the musculoskeletal system in horses. For relief of inflammatory conditions associated with the musculoskeletal system in horses.Intravenous dosage (not subcutaneous or intramuscular use):Horses: 1 to 2 g per 1,000 lb body weight (5 to 10 mL/1,000 lb) daily.Not for use in Horses intended for food.See package outsert for additional information.Approved by FDA under ANADA 200-371Each mL contains:Phenylbutazone ............................. 200 mgBenzyl Alcohol Preservative .........10.45 mgSodium hydroxide to adjust pH to 9.5 to 10.0Water For Injection ...............................q.s.
Active Ingredient(s)
  • Phenylbutazone
Marketing Category ANADA - ABBREVIATED NEW ANIMAL DRUG APPLICATION What is the Marketing Category?
Product types are broken down into several potential Marketing Categories, such as NDA/ANDA/BLA, OTC Monograph, or Unapproved Drug. One and only one Marketing Category may be chosen for a product, not all marketing categories are available to all product types. Currently, only final marketed product categories are included. The complete list of codes and translations can be found at under Structured Product Labeling Resources.
FDA Application Number ANADA200371 What is the FDA Application Number?
This corresponds to the NDA, ANDA, or BLA number reported by the labeler for products which have the corresponding Marketing Category designated. If the designated Marketing Category is OTC Monograph Final or OTC Monograph Not Final, then the Application number will be the CFR citation corresponding to the appropriate Monograph (e.g. “part 341”). For unapproved drugs, this field will be null.

Phenylbutazone Animal Product Labeling Information

The product labeling information includes all published material associated to a drug. Product labeling documents include information like generic names, active ingredients, ingredient strength dosage, routes of administration, appearance, usage, warnings, inactive ingredients, etc.

Table of Contents


CAUTION:  Federal law restricts this drug to use by or on the order of a licensed veterinarian.




Approved by FDA under ANADA # 200-371

DESCRIPTION: Phenylbutazone 20% Injection (phenylbutazone) is a synthetic, nonhormonal anti-inflammatory, antipyretic compound useful in the management of inflammatory conditions. The apparent analgesic effect is probably related mainly to the compound's anti-inflammatory properties.  Chemically, phenylbutazone is 4-butyl-1,2-diphenyl-3,5-pyrazolidinedione. It is a pyrazolon derivative entirely unrelated to the steroid hormones, and has the following structural formula:

Background Pharmacology

Kuzell, 1, 2, 3 Payne,4 Fleming,5 and Denko6 demonstrated clinical effectiveness of phenylbutazone in acute rheumatism, gout, gouty arthritis and various other rheumatoid disorders in man. Anti-rheumatic and anti-inflammatory activity has been well established by Fabre,7 Domenjoz,8 Wilhelmi,9 and Yourish.10  Lieberman 11 reported on the effective use of phenylbutazone in the treatment of painful conditions of the musculoskeletal system in dogs; including posterior paralysis associated with intervertebral disc syndrome, painful fractures, arthritis, and painful injuries to the limbs and joints. Joshua12 observed objective improvement without toxicity following long-term therapy of two aged arthritic dogs. Ogilvie and Sutter13 reported rapid response to phenylbutazone therapy in a review of 19 clinical cases including posterior paralysis, posterior weakness, arthritis, rheumatism, and other conditions associated with lameness and musculoskeletal weakness.

Camberos14 reported favorable results with phenylbutazone following intermittent treatment of Thoroughbred horses for arthritis and chronic arthrosis (e.g., osteoarthritis of medial and distal bones of the hock, arthritis of stifle and hip, arthrosis of the spine, chronic hip pains, achronic pain in the trapezius muscles, and generalized arthritis). Results were less favorable in cases of traumatism, muscle rupture, strains and inflammations of the third phalanx. Sutter15 reported favorable response in chronic equine arthritis, fair results in a severely bruised mare, and poor results in two cases where the condition was limited to the third phalanx


    For relief of inflammatory conditions associated with the musculoskeletal system in horses.

For relief of inflammatory conditions associated with the musculoskeletal system in horses.

Intravenous dosage (not subcutaneous or intramuscular use):

Horses: 1 to 2 g per 1,000 lb body weight (5 to 10 mL/1,000 lb) daily.

Not for use in Horses intended for food.

See package outsert for additional information.

Approved by FDA under ANADA 200-371

Each mL contains:Phenylbutazone ............................. 200 mg
Benzyl Alcohol Preservative .........10.45 mg
Sodium hydroxide to adjust pH to 9.5 to 10.0
Water For Injection ...............................q.s.


Treated animals should not be slaughtered for food purposes. Parenteral injections should be made intravenously only; do not inject subcutaneously or intramuscularly. Use with caution in patients who have a history of drug allergy.


Stop medication at the first sign of gastrointestinal upset, jaundice, or blood dyscrasia. Authenticated cases of agranulocytosis associated with the drug have occurred in man. To guard against this possibility, conduct routine blood counts at weekly intervals of two weeks thereafter. Any significant fall in th total white count, relative decrease in granulocytes, or black or tarry stools, should be regarded as a signal for immediate cessation of therapy and institution of appropriate counter measures. In the treatment of inflammatory conditions associated with infections, specific anti-infective therapy is required.

Storage And Handling

Store in refrigerator between 2o - 8oC (36o - 46oF)

Dosage And Administration

INTRAVENOUSLY: 1 to 2 g per 1,000 lbs of body weight (5 to 10 mL/1,000 lbs) daily. Injection should be given slowly and with care. Limit intravenous administration to a maximum of 5 successive days, which may be followed by oral phenylbutazone dosage forms.

1.  Use a relatively high dose for the first 48 hours, then reduce gradually to a maintenance dose. Maintain lowest dose capable of producing desired clinical response.
2.  Response to phenylbutazone therapy is prompt, usually occurring within 24 hours. If no significant clinical response is evident after 5 days, reevaluate diagnosis and therapeutic approach.
3.  In animals, phenylbutazone is largely metabolized in 8 hours. It is recommended that a third of the daily dose be administered at 8 hour intervals. Reduce dosage as symptoms regress. In some cases, treatment may be given only when symptoms appear with no need for continuous medication. If long-term therapy is planned, oral administration is suggested.
4.  Many chronic conditions will respond to phenylbutazone therapy, but discontinuance of treatment may result in recurrence of symptoms.

Contact Information

to report suspected adverse events for technical assistance or to obtain a copy of the Safety Data Sheet, contact Sparhawk Laboratories Inc. at 1-800-255-6388 or 1-913-888-7500. For additional information about adverse drug experience reporting for animal drugs, contact FDA at 1-888-FDA-VETS or

How Supplied

INJECTABLE: For Horses only: 100 mL vials, 200 mg/mL (1 g/5 mL) Each mL contians 200 mg of phenylbutazone, 10.45 mg of benzyl alcohol as preservative, sodium hydroxide to adjust pH to 9.5 to 10.0, and water for injection, Q.S.


1. Kuzell, W.C., Schaffarzick, R.W., Naugler, W.G., and Mankle, E.A.: AMA Arch. Int. Med. 92:646, 1953.
2. Kuzell, W.C., Schaffarzick, R.W., Brown, B. and Mankle, E.A.: Jour. Amer. Med. Assoc. 149:729, 1952.
3. Kuzell, W.C., Schaffarzick, R.W., Calif. Med. 777:319, 1952.
4. Payne, R.W., Shetlar, M.R., Farr, C., Hellbaum, A.A., and Ishmael, W.K.T.: J.Lab. Clin. Med. 45:331, 1955.
5. Fleming, J. and @Will, G.: Ann Rheumat. Dis. 12:95, 1953.
6. Denko, C.W., and Rumi, D.: Amer. Practit. 6:1865, 1955.
7. Fabre, J. and Berger, A.: Semaine Hop. (Paris) 31:87, 1955.
8. Domenjoz, R., Theobald, W. and Morsdorf, K., Arzneimittel-Forsch. 5:488, 1955.
9 Wilhelmi, G., and Pulver, R.: Arzneimittel-Forsch. 5:221, 1955.
10. Yoursh, N., Paton, B., Brodie, B.B and Burns, J.J.: AMA Arch. Ophth. 53:264, 1955.
11. Lieberman, L.L.: Jour. Amer. Vet. Med. Assoc. 125:128, 1954.
12. Joshua, J.O.: Vet. Rec. 68:60 (Jan 21), 1956.
13. Ogilvie, F.B. and Sutter, M.D.: Vet. Med 52:492-494, 1957.
14. Camberos, H.R.: Rev. Med. Vet. (Buenos Aires); 38:9, 1956.
15. Sutter, M.F.: Vet Med. 53:83 (Feb.), 1958.

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