ISSN 2398-2977      

Phenylbutazone

pequis

Introduction

Name

  • Phenylbutazone.

Class of drug

  • Non-steroidal anti-inflammatory.

Description

Chemical name

  • 4-butyl-1,2-diphenyl-pyrazolidine-3,5-dione.

Molecular formula

  • C19H20N2O2.

Molecular weight

  • 308.374 g/mol.

Physical properties

  • Lipophilic.

Storage requirements

  • Room temperature.

Uses

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Indications

  • Inflammation, pain and pyrexia.

Some authorities, including the Jockey Club, regard phenylbutazone as a 'prohibited substance' under the rules of competition. Therefore, use of this product in a competition horse should be in accordance with the recommendations/advice of the relevant competition authorities. The clinical effect of phenylbutazone can be evident for at least three days following cessation of administration. This should be bourne in mind when examining horses for soundness.

Administration

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Pharmacokinetics

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Precautions

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Interactions

with other drugs

Drugs affecting phenylbutazone
  • Barbiturates - decreased metabolism.
  • Cardiac glycosides - increased metabolism and decreased effect.
  • Chloramphenicol - decreased metabolism.
  • Colestyramine - decreased enteral absorption.
  • Corticosteroids, other NSAIDs and sulfonamides - displacement from plasma proteins and increased effect.

Drugs affected by phenylbutazone

  • Phenylbutazone is extensively bound to plasma proteins; it may displace other drugs that are highly protein-bound, or it may itself be displaced to produce an increase in non-bound pharmacologically active concentrations which can lead to toxic effects.
  • Concurrent therapy with other therapeutic agents should be undertaken with caution due to the risk of metabolic interactions. There is evidence to indicate that the pharmacokinetics of penicillin and gentamicin products may be affected by concurrent administration of products containing phenylbutazone with a possible reduction of therapeutic efficacy, since tissue penetration may be reduced.
  • The distribution of other drugs given concurrently may also be affected.
  • Phenylbutazone induces hepatic microsomal enzyme activity.
  • Methotrexate Methotrexate - decreased excretion.
  • Penicillins Penicillin G - altered half-life and tissue penetration.
  • Phenytoin Phenytoin - decreased metabolism.
  • Sulfonylureas - increased hypoglycemic effect.
  • Levothyroxine Levothyroxine - falsely low plasma-total levothyroxine.
  • Warfarin Warfarin - increased anticoagulant effect.

Adverse Reactions

This article is available in full to registered subscribers

Sign up now to obtain ten tokens to view any ten Vetlexicon articles, images, sounds or videos, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Authie E C et al (2010) Effect of an endurance-like exercise on the disposition and detection time of phenylbutazone and dexamethasone in the horse: Application to medication control. Equine Vet J 42 (3), 240-247 PubMed.
  • Sabate D, Homedes J, Salichs M, Sust M & Monreal L (2009) Multicentre, controlled, randomised and blinded field study comparing efficacy of suxibuzone and phenylbutazone in lame horses. Equine Vet J 41 (7), 700-705 PubMed.
  • Conwell R & Stratford C (2008) Right dorsal colitis. Vet Rec 13 (8), 7-10.

Other sources of information

  • Derived from The Veterinary Formulary (1998) 4th edn. Ed: Bishop Y. British Veterinary Association and Royal Pharmaceutical Society.

Related Images

RELATED CONTENT

Abdomen: adhesions

Abdomen: surgical approaches

Accessory ligament DDFT: desmotomy

Accessory ligament DDFT: forelimb - desmitis

Accessory ligament SDFT: desmotomy

Anemia: overview

Anesthesia: analgesia - overview

Anesthesia: peri-operative complications

Annular ligament: transection - palmar / plantar

Benzylpenicillin

Bladder: urinary tract infection

Blood: platelet evaluation

Bone: physitis

Borreliosis

Candidiasis

Carotid artery: intracarotid injection

Carpus: chip removal

Carpus: fracture - chip

Carpus: sheath tenosynovitis

Cecum: typhlectomy

Cecum: typhlotomy

Cellulitis

Common digital extensor tendon: rupture

Cranial nuchal bursa bursoscopy

Deep digital flexor tendon: tendinitis

Deep digital flexor tendon: tenotomy

Dermatology: intradermal test

Digital sheath: tenosynovitis

DIP joint: flexural deformity

Distal phalanx: fracture repair

Distal phalanx: fractures

Distal phalanx: pedal osteitis - septic

Elbow: osteoarthritis

Endocrine: hypothyroidism

Endocrine: T3 assay

Endocrine: T4 assay

Endotoxemia: overview

Epiglottis: entrapment - repair

Equine viral encephalitides

Esophagus: obstruction

Ethmoid: hematoma

Extensor carpi radialis muscle: rupture

Eye: dermoid excision

Eye: glaucoma

Eye: intraocular prosthesis

Eyeball: enucleation - transconjunctival

Flexor tendon: trauma

Foal: resuscitation and care

Foot: hoof wall - crack repair

Foot: keratoma - resection

Foot: laminitis

Foot: sole bruising

Foot: subsolar abscess/infection

Gastrointestinal: ileus

Grass sickness

Hard palate: palatitis

Hematoma

Joint: septic arthritis - adult

Keratitis: bacterial

Keratitis: traumatic - ulcerative

Larynx: arytenoidectomy

Larynx: ventriculocordectomy

Laser surgery: transendoscopic

Leptospirosis

Levothyroxine

Lung: pleuropneumonia - bacterial (pleuritis)

Lung: pneumonia - neonatal bacterial

Lymphangitis

Male: ejaculatory dysfunction

Mammary gland: mastitis

MC / MT 2 and 4: fracture repair

MC / MT 2 and 4: partial removal

MC / MT 3: condylar fracture repair

MC / MT 3: diaphysis fracture

MC / MT 3: dorsal metacarpal disease

MC / MT 4: removal

MC/MT 2 and 4: fracture

MC/MT 2 and 4: periostitis (splints)

MCP / MTP joint: chronic proliferative synovitis

MCP / MTP joint: flexural deformity

MCP/MTP joint: luxation

Medial patellar ligament: desmotomy

Methotrexate

Muscle: myopathy - fibrotic

Muscle: myopathy - sporadic exertional rhabdomyolysis

Musculoskeletal: back pain

Musculoskeletal: fracture - first aid

Musculoskeletal: osteoarthritis (joint disease)

Navicular bone: suspensory desmotomy

Navicular bone: syndrome

Navicular bursa: puncture

Omentectomy

Orbit: trauma

Palmar carpal retinaculum: section

Palmar digital nerve: neurectomy

Patella: fracture

Patella: fragmentation

Pelvis: fracture

Pelvis: trauma - sacroiliac

Penis: phallectomy - Scott's technique

Penis: phallectomy - Vinscot technique

Penis: phallectomy - William technique

Perineum: trauma - repair

Peripheral nerve: trauma

Pharynx: ventral pharyngotomy

Phenytoin

Photoactivated vasculitis

PIP joint: arthrodesis

PIP joint: luxation

PIP joint: osteoarthritis

Placenta: retained

Prepuce: resection

Proximal phalanx: fracture

Proximal sesamoid: fracture

Proximal sesamoid: fracture - arthroscopic removal

Purpura hemorrhagica

Rectum: meconium impaction

Reproduction: gamete intrafallopian transfer

Reproduction: oocyte transfer

Respiratory: anesthesia

Respiratory: meconium aspiration

Respiratory: neonatal respiratory distress syndrome

Respiratory: smoke inhalation

Sacrum: fracture

Sciatic nerve: paralysis

SDFT: luxation

SDFT: tendinitis

Spine: cervical vertebral malformation (CVM)

Spine: fracture

Sternum: bone graft collection

Stifle: femoropatellar osteochondrosis

Stifle: femorotibial subchondral bone cyst

Stifle: trauma - collateral ligament

Stifle: trauma - cruciate ligament

Stifle: trauma - meniscal

Stomach: gastric ulceration

Straight sesamoidean ligament: desmitis

Suprascapular nerve: paralysis

Suspensory ligament: desmitis - midbody

Suspensory ligament: desmitis - proximal

Tarsus: arthrodesis

Tarsus: desmitis - plantar ligament

Tarsus: distal tarsal bone fracture / luxation

Tarsus: fracture

Tarsus: osteoarthritis (bone spavin)

Tarsus: tarsal sheath tenosynovitis

Testis: castration - post-operative complications

Testis: orchitis

Therapeutics: anti-inflammatory drugs

Therapeutics: gastrointestinal system

Therapeutics: skin

Tibia: bone graft collection

Tibia: fracture - tibial crest

Toxicity: anticoagulant rodenticide

Toxicity: non-steroidal anti-inflammatory (NSAID)

Tuber coxae: bone graft collection

Ulna: fracture

Ulnaris lateralis: tenotomy - flexural deformity

Urticaria/angiedema

Uterus: caesarean section

Uveitis: traumatic

Vasculitis

Vesicular stomatitis

Warfarin sodium

Wound: post-operative care

Want more related items, why not
contact us

MEMBER BENEFIT

Can’t find what you’re looking for?

We have an ever growing content library on Vetlexicon so if you ever find we haven't covered something that you need please fill in the form below and let us know!

 
 
 
 

To show you are not a Bot please can you enter the number showing adjacent to this field

 Security code