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Home / Equine Research Bank / Ir Vet J / Aminorex identified in horse urine following consumption of ...
Irish veterinary journal2019; 72; 15; doi: 10.1186/s13620-019-0153-5

Aminorex identified in horse urine following consumption of Barbarea vulgaris; a preliminary report.

Abstract: Aminorex, (RS)-5- Phenyl-4,5-dihydro-1,3-oxazol-2-amine, is an amphetamine-like anorectic and in the United States a Drug Enforcement Administration [DEA] Schedule 1 controlled substance. Aminorex in horse urine is usually present as a metabolite of Levamisole, an equine anthelmintic and immune stimulant. Recently, Aminorex identifications have been reported in horse urine with no history or evidence of Levamisole administration. Analysis of the urine samples suggested a botanical source, directing attention to the Brassicaceae plant family, with their contained GlucoBarbarin and Barbarin as possible sources of Aminorex. Since horsepersons face up to a 1 year suspension and a $10,000.00 fine for an Aminorex identification, the existence of natural sources of Aminorex precursors in equine feedstuffs is of importance to both individual horsepersons and the industry worldwide. Results: Testing the hypothesis that Brassicaceae plants could give rise to Aminorex identifications in equine urine we botanically identified and harvested flowering Kentucky , ("Yellow Rocket") in May 2018 in Kentucky and administered the plant orally to two horses. Analysis of post-administration urine samples yielded Aminorex, showing that consumption of Kentucky can give rise to Aminorex identifications in equine urine. Conclusions: Aminorex has been identified in post administration urine samples from horses fed freshly harvested flowering Kentucky , colloquially "Yellow Rocket". These identifications are consistent with occasional low concentration identifications of Aminorex in equine samples submitted for drug testing. The source of these Aminorex identifications is believed to be the chemically related Barbarin, found as its precursor GlucoBarbarin in Kentucky and related Brassicaceae plants worldwide.
© The Author(s). 2019.
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Publication Date: 2019-12-23 PubMed ID: 31890155PubMed Central: PMC6929286DOI: 10.1186/s13620-019-0153-5Google 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.

Research has discovered that the controlled substance Aminorex can be found in horse urine after they consume a common plant called Barbarea vulgaris. Further tests validated that these plants, originating from the Brassicaceae family, can indeed lead to the presence of Aminorex in horse urine.

Background

  • The substance Aminorex is a Schedule 1 controlled substance in the United States, recognized for its amphetamine-like properties.
  • Generally found in horse urine as a metabolite of Levamisole, it has been recently noted in horses’ urine without prior Levamisole administration.
  • After studying the urine samples, researchers speculated that the source of Aminorex could be botanical, thus linking it to the Brassicaceae plant family, specifically GlucoBarbarin and Barbarin, which are considered potential sources of Aminorex.
  • As detection of Aminorex in horses could lead to a hefty fine and suspension for horse handlers, the discovery of natural sources of this substance in horse feeds becomes significantly important to the equine industry globally.

The Study and Results

  • Researchers tested their hypothesis that Brassicaceae plants could lead to the detection of Aminorex in horse urine.
  • They harvested flowerings of a plant known as Kentucky or “Yellow Rocket” and orally administered it to two horses.
  • Post-administration urine sample analysis confirmed the presence of Aminorex, hence validating the hypothesis that eating Kentucky can cause Aminorex detection in horse urine.

Conclusion

  • The study affirmed that Aminorex could indeed be identified in the urine samples of horses that consumed freshly harvested Kentucky or “Yellow Rocket”.
  • These findings explained the occasional detection of Aminorex in low concentrations in equine sample tests.
  • Researchers accredited the presence of Aminorex to the chemically associated Barbarin, found as a precursor GlucoBarbarin in the Kentucky plant and other related plants from the Brassicaceae family worldwide.

Cite This Article

APA
Maylin G, Fenger C, Machin J, Kudrimoti S, Eisenberg R, Green J, Tobin T. (2019). Aminorex identified in horse urine following consumption of Barbarea vulgaris; a preliminary report. Ir Vet J, 72, 15. https://doi.org/10.1186/s13620-019-0153-5

Publication

Irish veterinary journal
ISSN: 0368-0762
NlmUniqueID: 0100762
Country: Ireland
Language: English
Volume: 72
Pages: 15
PII: 15

Researcher Affiliations

Maylin, George
  • New York Drug Testing and Research Program, 777 Warren Rd, Ithaca, NY 14853 USA.
Fenger, Clara
  • Equine Integrated Medicine, 4904 Ironworks Rd, Georgetown, KY 40324 USA.
Machin, Jacob
  • 3The Maxwell H. Gluck Equine Research Center and Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40546 USA.
Kudrimoti, Sucheta
  • 3The Maxwell H. Gluck Equine Research Center and Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40546 USA.
Eisenberg, Rodney
  • Frontier BioPharm, LLC, Richmond, KY 40475 USA.
Green, Jonathan
  • 5Department of Plant and Soil Sciences, University of Kentucky, Lexington, KY 40546 USA.
Tobin, Thomas
  • 3The Maxwell H. Gluck Equine Research Center and Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, KY 40546 USA.

Conflict of Interest Statement

Competing interestsThe authors declare that they have no competing interests.

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Citations

This article has been cited 4 times.
  1. Brewer K, Machin J, Maylin G, Fenger C, Morales-Briceño A, Tobin T. Gabapentin, a human therapeutic medication and an environmental substance transferring at trace levels to horses: a case report. Ir Vet J 2022 Oct 4;75(1):19.
    doi: 10.1186/s13620-022-00226-5pubmed: 36192810google scholar: lookup
  2. Kudrimoti S, Machin J, Arojojoye AS, Awuah SG, Eisenberg R, Fenger C, Maylin G, Lehner AF, Tobin T. Synthesis and characterization of d(5) -barbarin for use in barbarin-related research. Drug Test Anal 2023 Jan;15(1):42-46.
    doi: 10.1002/dta.3357pubmed: 35975356google scholar: lookup
  3. Waller P, Lomnicka I, Lucas C, Johnson S, Dirikolu L. The medication violations in racehorses at Louisiana racetracks from 2016 to 2020. Vet Med Sci 2022 Mar;8(2):553-560.
    doi: 10.1002/vms3.724pubmed: 34989156google scholar: lookup
  4. Brooks L, Ryan M, McCosham E, Loganathan D. Further Investigation Into an Environmental Source for Aminorex. Drug Test Anal 2025 Aug;17(8):1357-1367.
    doi: 10.1002/dta.3820pubmed: 39696754google scholar: lookup
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