FEI - WARNING ABOUT SYNEPHRINE

Wednesday 15 May 2019

The FEI is warning the equestrian community about synephrine, which is a Banned Substance listed on the Equine Prohibited Substances List.

A high number of samples taken from horses under the Equine Anti-Doping and Controlled Medication Programme have tested positive for the substance. Investigations into the sources of the positive cases are continuing but the FEI is warning that synephrine can be found in the horse’s environment so it is advising of how to prevent a positive finding.

Synephrine is a stimulant which can cause vasoconstriction, an increased heart rate and is used as a weight loss aid.

In certain parts of the world, synephrine can be found in plants such as common rush (Juncus usitatus), Mullumbimby couch (Cyperus brevifolus) and the leaves of citrus trees (e.g. mandarin, orange and lemon). Synephrine has also been detected in Teff grass hay in some countries.

 

It can also be found as an ingredient of herbal and nutritional supplements, and commonly found in the peel extract of bitter orange (also known as Seville orange) which is used as a flavouring agent.

 

How to prevent positive findings:

  • Use reputable suppliers of hay, feed and supplements.
  • Check the horse’s environment for plants containing synephrine.
  • Ensure that any personnel taking supplements or other products containing synephrine wash their hands thoroughly after coming into contact with the substance.

Additionally, it is recommended that samples are kept of batches of hay, feed and supplements given to competition horses to enable a thorough investigation to take place should the horse test positive for synephrine.

Further information concerning contamination prevention can be found here.

 


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