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Veterinary Toxicology and Pharmacology

Maxwell H. Gluck Equine Research Center Faculty Publications

Equine pharmacology

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Articles 1 - 2 of 2

Full-Text Articles in Large or Food Animal and Equine Medicine

An Overview Of The Methylxanthines And Their Regulation In The Horse, J Daniel Harkins, W. Allen Rees, G. D. Mundy, Scott D. Stanley, Thomas Tobin Jan 1998

An Overview Of The Methylxanthines And Their Regulation In The Horse, J Daniel Harkins, W. Allen Rees, G. D. Mundy, Scott D. Stanley, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

Caffiene, theophylline and theobromine are naturally occurring members of the methylxanthine family;pentoxfylline, dyphylline and enprofylline are structurally related synthetic pharmaceuticals. Caffiene has predominantly central nervous system effects, theophylline, dyphylline and enprofylline have predominantly bronchodilator effects, while theobromine is associated with diuretic responses. Pentoxfylline is thought to increase red cell deformability and facillitate blood flow through capillary beds. The methylxanthines are not highly potent agents; they are typically administered in gram doses and they tend to have relatively long half-lives. They remain detectable in plasma and urine for relatively long periods. Similarly, traces of the naturally occurring members of this family …


Phenylbutazone In The Horse: A Review, Thomas Tobin, S. Chay, S. Kamerling, W. E. Woods, T. J. Weckman, J. W. Blake, P. Lees Jan 1986

Phenylbutazone In The Horse: A Review, Thomas Tobin, S. Chay, S. Kamerling, W. E. Woods, T. J. Weckman, J. W. Blake, P. Lees

Maxwell H. Gluck Equine Research Center Faculty Publications

Phenylbutazone is an acidic, lipophilic, nonsteroidal anti-inflammatory drug (NSAID). It is extensively metabolized in the horse. The metabolites so far identified, oxyphenbutazone, y-hydroxyphenylbutazone and y-hydroxyoxyphenbutazone. account for some 25-30% of administered dose over 24 h. The plasma half-life of phenylbutazone and termination of its pharmacological action are determined primarily by its rate of hepatic metabolism. Phenylbutazone acts by inhibiting the cyclooxygenase enzyme system, which is responsible for synthesis of prostanoids such as PGE?. It appears to act on prostaglalidin-H synthase and prostacyclin synthase, after conversion by prostaglandin-H synthase to reactive intermediates. It markedly reduces prostanoid-dependent swelling, edema, erythema, and hypersensitivity …