The popular feed supplement ingredient Dimethyl sulpone, commonly known as MSM, will be removed from the FEI Equine Prohibited Substances List (EPSL) effective January 1, 2018.

The move follows considerable lobbying by the British Equestrian Trade Association (BETA) Feed Committee, which provided extensive technical evidence in support of their belief that defining MSM as a prohibited substance would negatively impact the equine industry.

MSM, an organic sulphur compound, occurs naturally in plants such as alfalfa, oats, and apples, is commonly used in equine diets, and has been used for three decades in both equine and human nutrition.

The official Fédération Equestre Internationale (FEI) press release states:

“The Equine Anti-Doping and Controlled Medication Regulations define a Controlled Medication Substance as ‘any substance, or its metabolites or markers, so described in the Equine Prohibited Substances List. Controlled Medication Substances are considered therapeutic and/or commonly used in equine medicine substances, and considered to have: (a) the potential to affect performance, and/or (b) a potential welfare risk to the horse. Controlled Medication Substances are prohibited In-Competition, but may be exceptionally permitted In-Competition when their use has been authorised by the appropriate Veterinary Form.'

The controlled medication under its chemical name Dimethyl sulpone, more commonly known as MSM, is a substance known to be an additive in certain feeds and naturally occurring. Dimethyl sulphone is often referred to as MSM.

The FEI Equine Prohibited Substance List is 'revised by a group of experts (List Group) who propose changes to the FEI Bureau once a year, in accordance with Art 4.2 EADCMR. The FEI Bureau approved the recommendation from the List Group to remove Dimethyl sulpone from the Controlled Medication List. The reclassification will be effective as of 1 January, 2018.'”

For more information, visit the FEI list of changes to the 2017 FEI EPSL to become effective January 1, 2018.

With files from, FEI

Photo: Shutterstock/Sharon Kingston



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