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Home / Equine Research Bank / J Vet Pharmacol Ther / The pharmacokinetics of xylazine hydrochloride: an interspec...
Journal of veterinary pharmacology and therapeutics1981; 4(2); 87-92; doi: 10.1111/j.1365-2885.1981.tb00715.x

The pharmacokinetics of xylazine hydrochloride: an interspecific study.

Abstract: The pharmacokinetic disposition of xylazine hydrochloride is described after both intravenous and intramuscular injection of a single dose, in four domestic species: horse, cattle, sheep and dog, by an original high performance liquid chromatographic technique. Remarkably small interspecific differences are reported. After intravenous administration, systemic half-life (t1/2 beta) ranged between 22 min (sheep) and 50 min (horse) while the distribution phase is transient with half-life (t1/2 alpha) ranging from 1.2 min (cattle) to 5.9 min (horse). The peak level of drug concentration in the plasma is reached after 12-14 min in all the species studied following intramuscular administration. Xylazine bioavailability, as measured by the ratios of the areas under the intravenous and intramuscular plasma concentration versus time curves, ranged from 52% to 90% in dog, 17% to 73% in sheep and 40% to 48% in horse. The low dosage in cattle did not permit calculation. Kinetic data are correlated with clinical data and the origins of interspecific differences are discussed.
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Publication Date: 1981-06-01 PubMed ID: 7349331DOI: 10.1111/j.1365-2885.1981.tb00715.xGoogle Scholar: Lookup
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  • Journal Article
  • Research Support
  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research article describes a study conducted to examine the pharmacokinetic disposition or how the drug xylazine hydrochloride moves in the body after a single dose of intravenous and intramuscular injection in four different domestic species: horses, cattle, sheep, and dogs. This is achieved using a unique high-performance liquid chromatographic technique. The study also discusses the minor differences observed between the species.

Methodology

  • The researchers use a method called high-performance liquid chromatography, a technique in analytical chemistry used to separate, identify, and quantify each component in a mixture. It is used to measure the rates of drug absorption in the different domestic species.
  • Xylazine hydrochloride was administered in two ways – intravenously and intramuscularly. These two methods allowed the researchers to compare how the drug is absorbed and circulated through the body in different ways.

Findings

  • The study reports minor differences in how the species process the drug. For example, after intravenous administration, the systemic half-life, which refers to the time a drug takes to decrease by half in the body, ranged from 22 minutes in sheep to 50 minutes in horses.
  • The distribution phase, or time taken for the drug to be dispersed throughout the body, is brief—ranging from 1.2 minutes in cattle to 5.9 minutes in horses.
  • The peak level of drug concentration in the plasma is reached after 12-14 minutes following intramuscular administration in all the species studied.

Comparison of Bioavailability

  • Bioavailability refers to the extent and rate at which a drug is absorbed and becomes available at the site of drug action. The bioavailability of Xylazine was measured by comparing the areas under the intravenous and intramuscular plasma concentration versus time curves.
  • In dogs, the bioavailability of Xylazine ranged from 52% to 90%, in sheep it was from 17% to 73%, and in horses, it was from 40% to 48%. A low dosage in cattle made it impossible to calculate the same.

Correlation of Kinetic Data with Clinical Data

  • The research also discussed the correlation of the kinetic data (the speed of absorption, distribution, and excretion of the drug) with clinical data and the causes of the small differences between the species. However, the abstract does not provide details about these specific findings.

Cite This Article

APA
Garcia-Villar R, Toutain PL, Alvinerie M, Ruckebusch Y. (1981). The pharmacokinetics of xylazine hydrochloride: an interspecific study. J Vet Pharmacol Ther, 4(2), 87-92. https://doi.org/10.1111/j.1365-2885.1981.tb00715.x

Publication

Journal of veterinary pharmacology and therapeutics
ISSN: 0140-7783
NlmUniqueID: 7910920
Country: England
Language: English
Volume: 4
Issue: 2
Pages: 87-92

Researcher Affiliations

Garcia-Villar, R
    Toutain, P L
      Alvinerie, M
        Ruckebusch, Y

          MeSH Terms

          • Animals
          • Biological Availability
          • Cattle / metabolism
          • Dogs / metabolism
          • Horses / metabolism
          • Injections, Intramuscular
          • Injections, Intravenous
          • Kinetics
          • Sheep / metabolism
          • Species Specificity
          • Thiazines / metabolism
          • Xylazine / blood
          • Xylazine / metabolism

          Citations

          This article has been cited 20 times.
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