USEF Prohibits MPA Use

The USEF Board of Directors voted to prohibit the use of Medroxyprogesterone Acetate (MPA) in horses competing at licensed competitions. The prohibition goes into effect December 1, 2019; however, due to the length of time it takes for MPA to clear a horses’ system, sanctions for positive test results will go into effect June 1, 2020. MPA is now classified as a Category III substance, punishable with a penalty range starting at a three to six month suspension and a fine of $3,000 to $6,000 for a first offense.

Following reports of equine fatalities and anaphylaxis related to MPA use, the USEF’s MPA panel met October 22 and further analyzed MPA usage in competition horses. The panel reviewed a recent petition by veterinarians requesting that the USEF ban MPA – the petition was supported by documentation citing 23 MPA-related fatalities over the past three years, research on MPA’s efficacy, and results from the collection of MPA medication reports.

The panel determined MPA has no therapeutic use in competition horses, because it does not interrupt estrus in mares – its original intended purpose. MPA is not approved by the FDA for equine use and its use has been associated with several cases of anaphylaxis and fatality. With this analysis, the panel unanimously voted to recommend MPA be added to the USEF’s prohibited substances list.

Said USEF president Murray Kessler, “In 2017, we debated the use of this substance and its efficacy, but now, with numerous fatalities associated with the use of MPA, this decision became clear: MPA must be banned. I commend the Panel for confronting a difficult task that involved very strong opinions on both sides of the issue from our membership. The information clearly supports the prohibition of this substance and I am proud of the decision of the Board of Directors. USEF has a responsibility to ensure the welfare of our horses, and the loss of one horse resulting from the use of a non-therapeutic substance such as MPA is one too many.”