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Journal of veterinary pharmacology and therapeutics2023; 46(4); 201-217; doi: 10.1111/jvp.13397

A review of current chemistry, pharmacology, and regulation of endogenous anabolic steroids testosterone, boldenone, and nandrolone in horses.

Abstract: Anabolic androgenic steroids are synthetic substances related to the male sex hormones (androgens). These agents promote the growth of skeletal muscle (anabolic effects) and the development of male sexual characteristics (androgenic effects). Anabolic steroids have been illegally used for many years as performance-enhancing drugs in human, equine, and canine sports and as growth promoters in livestock reared to provide meat for human consumption. The analytical challenge to developing effective means of control within these fields has been exacerbated by the reported endogenous nature of some of these steroids. Anabolic steroids have been employed extensively in equine practice over the past 50 years. Their usefulness is largely dependent on subjective opinions, as only minimal studies investigating pharmacodynamics have been carried out in horses. Therefore, their use will vary markedly between practitioners depending on their personal experiences and pressures by trainers to use them. They form part of rational therapy in a variety of conditions. In addition to their use for increasing muscle mass, they are used to varying extents in the raising of yearlings and in the training and racing of horses with the view of improving performance. The use of these agents is prohibited in the horseracing industry by the Association of Racing Commissioners International (ARCI), International Federation of Horseracing Authorities (IFHA), and Fédération Equestre Internationale (FEI).
© 2023 John Wiley & Sons Ltd.
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Publication Date: 2023-06-01 PubMed ID: 37264491DOI: 10.1111/jvp.13397Google Scholar: Lookup
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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 explores the use, effects, and regulation of anabolic androgenic steroids, specifically testosterone, boldenone, and nandrolone, in horses. It touches on their role in enhancing performance in equestrian sports and growth in livestock, as well as the challenges in monitoring and controlling their use due to their endogenous nature.

Understanding Anabolic Androgenic Steroids

  • Anabolic androgenic steroids are synthetic substances tied to male sex hormones, known as androgens. They aid in muscle growth (anabolic effect) and the development of male sexual characteristics (androgenic effect).
  • These steroids have been misused for performance enhancement in human, equine, and canine sports. They are also used as growth boosters in livestock meant for human consumption.
  • The control and monitoring of these substances pose analytical challenges, in part because some of these steroids are endogenous, meaning they’re produced by organisms naturally.

The Use of Anabolic Steroids in Horses

  • For the past five decades, the use of anabolic steroids in horses has been extensive.
  • The degree of their usefulness is largely based on subjective views, as there is a minimal amount of studies looking into the pharmacodynamics of these substances in horses.
  • The use of these steroids varies greatly among practitioners depending on personal experiences and pressure from trainers.
  • These agents are used as part of treatment for different conditions. Beyond muscle mass improvement, they’re used in raising yearlings and in the training and racing of horses to enhance performance.

Regulations Regarding Anabolic Steroids in Horseracing

  • The use of anabolic steroids in horseracing is prohibited by various organizations like the Association of Racing Commissioners International (ARCI), International Federation of Horseracing Authorities (IFHA), and Fédération Equestre Internationale (FEI).

Cite This Article

APA
Dirikolu L, Lehner AF. (2023). A review of current chemistry, pharmacology, and regulation of endogenous anabolic steroids testosterone, boldenone, and nandrolone in horses. J Vet Pharmacol Ther, 46(4), 201-217. https://doi.org/10.1111/jvp.13397

Publication

Journal of veterinary pharmacology and therapeutics
ISSN: 1365-2885
NlmUniqueID: 7910920
Country: England
Language: English
Volume: 46
Issue: 4
Pages: 201-217

Researcher Affiliations

Dirikolu, Levent
  • Department of Comparative Biomedical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana, USA.
Lehner, Andreas F
  • MSU Veterinary Diagnostic Laboratory, Section of Toxicology, Michigan State University, East Lansing, Michigan, USA.

MeSH Terms

  • Horses
  • Animals
  • Male
  • Dogs
  • Humans
  • Anabolic Androgenic Steroids
  • Nandrolone / pharmacology
  • Doping in Sports
  • Testosterone
  • Androgens / pharmacology
  • Steroids / chemistry
  • Anabolic Agents / pharmacology
  • Anabolic Agents / chemistry

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Citations

This article has been cited 3 times.
  1. Roccaro M, Rinnovati R, Stucchi L, La Rocca F, Cascio G, Peli A. Survey on 9 years of anti-doping controls in horse races in Italy. Equine Vet J 2025 Nov;57(6):1592-1599.
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  2. Ishii H, Shigematsu R, Takemoto S, Ishikawa Y, Mizobe F, Nomura M, Arima D, Kunii H, Yuasa R, Yamanaka T, Tanabe S, Nagata SI, Yamada M, Leung GN. Quantification of osilodrostat in horse urine using LC/ESI-HRMS to establish an elimination profile for doping control. Bioanalysis 2024;16(17-18):947-958.
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  3. Klöppner L, Harps LC, Parr MK. Sample Preparation Techniques for Growth-Promoting Agents in Various Mammalian Specimen Preceding MS-Analytics. Molecules 2024 Jan 9;29(2).
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