Imidocarb has been used for years to treat or limit the symptoms of this disease. Although its therapeutic value is not disputed, the FEI now classifies it as a controlled substance because it may influence equine performance. Another factor is that residues of the product can remain detectable in the blood for months, sometimes up to half a year after administration. This raised fears that treated horses could be excluded from international competitions for long periods. Some top riders have therefore reportedly already decided not to enter recently treated horses for the time being.

The FEI stresses that substances are not added to its list arbitrarily. Each year, a specialised working group composed of veterinarians, pharmacologists, researchers, and representatives of accredited laboratories evaluates the available scientific knowledge. On that basis, the FEI Board decides on possible additions. According to the federation, imidocarb meets the criteria because, in addition to its medical uses, it also carries risks, including known toxic side effects and reports of use outside strict veterinary supervision. In some disciplines, the drug is also said to have been administered deliberately to temporarily improve horses’ condition.

At the same time, the FEI wants to make clear that necessary treatments must not be compromised. The federation is currently working with laboratories on a scientifically grounded withdrawal period and a possible detection threshold, so that the drug can be used responsibly without risking sporting sanctions. Until those guidelines are published, the FEI advises veterinarians not to postpone treatments when there is a medical indication and to record all administrations carefully.

The aim is therefore not to ban the use of imidocarb, but to establish clear rules on when a treated horse may return to international competition. During the transitional period, it also appears likely that positive tests will not automatically lead to disciplinary proceedings.