Effects of phenylbutazone alone or in combination with flunixin meglumine on blood protein concentrations in horses.
OBJECTIVE
To assess effects of treatment with phenylbutazone (PBZ) or a combination of PBZ and flunixin meglumine in horses.


METHODS
24 adult horses.


METHODS
13 horses received nonsteroidal antiinflammatory drugs (NSAIDs) in a crossover design. Eleven control horses were exposed to similar environmental conditions. Treated horses received PBZ (2.2 mg/kg, PO, q 12 h, for 5 days) and a combination of PBZ and flunixin meglumine (PBZ, 2.2 mg/kg, PO, q 12 h, for 5 days; flunixin meglumine, 1.1 mg/kg, IV, q 12 h, for 5 days). Serum samples were obtained on day 0 (first day of treatment) and day 5, and total protein, albumin, and globulin were measured.


RESULTS
1 horse was euthanatized with severe hypoproteinemia, hypoalbuminemia, and colitis during the combination treatment. Comparisons revealed no significant difference between control horses and horses treated with PBZ alone. There was a significant difference between control and treated horses when administered a combination of PBZ and flunixin meglumine. Correction for horses with values >2 SDs from the mean revealed a significant difference between control horses and horses administered the combination treatment, between control horses and horses administered PBZ alone, and between horses receiving the combination treatment and PBZ alone. Gastroscopy of 4 horses revealed substantial gastric ulcers when receiving the combination NSAID treatment.


CONCLUSIONS
Analysis of results of the study indicates the need for caution when administering a combination NSAID treatment to horses because the detrimental effects may outweigh any potential benefits.
Reed
Shannon K
SK
Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, 65211, USA.
Messer
Nathaniel T
NT
Tessman
Ronald K
RK
Keegan
Kevin G
KG
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology*; D001798:Blood Proteins / Q000032:analysis; D003002:Clonixin / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000494:pharmacology; D004359:Drug Therapy, Combination; D005260:Female; D006734:Horse Diseases / Q000097:blood / Q000139:chemically induced / Q000473:pathology; D006736:Horses / Q000097:blood*; D034141:Hypoalbuminemia / Q000139:chemically induced; D007019:Hypoproteinemia / Q000139:chemically induced; D008297:Male; D010653:Phenylbutazone / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology*; D013276:Stomach Ulcer / Q000139:chemically induced / Q000662:veterinary
D000894:Anti-Inflammatory Agents, Non-Steroidal; D001798:Blood Proteins; C014558:flunixin meglumine; D010653:Phenylbutazone; D003002:Clonixin