top of page

Plant Chemicals on the FEI/BHA Banned Substances List

Updated: Feb 2

The FEI and BHA banned substance list is the go-to place for riders and vets who need to check whether medications are safe to use during competitions. The FEI and BHA Banned Substances list also includes Controlled Substances. 

When riders think of “banned substances”, they often - rightly - think of medications, supplements and hard feed as being potential triggers for a positive drug test. However, did you know that both banned and controlled substances can be found in commonly accessed pasture plants?

This blog article provides some examples of commonly accessed pasture plants that contain banned substances.

An example of how of Common Plant Chemicals can Appear on the FEI Banned Substances List

Plants make many powerful chemicals and they are commonly used as a basis for manufacturing synthetic drugs. In a drug test, the source (i.e. natural or synthetic) won't matter and the horse will fail a drug test regardless. How easy is it for the horse to unknowingly get access to common drugs through the ingestion of a plant?

Here is an example of how common plant chemicals can appear on the FEI/BHA banned substance list:

Coumarin is on the FEI prohibited/banned substances list and its activity is described as an anticoagulant. The medical dictionary defines coumarin as a ‘toxic white crystalline lactone C9H6O2 with an odour of new-mown hay found in plants or made synthetically and used especially in perfumery and as the parent compound in various anticoagulant agents (warfarin)’

The synthetic drug Warfarin, which is also on the FEI prohibited list, was originally developed from a spoiled clover crop that contained a bacterial metabolite of coumarin over 50 years ago.

Both the FEI and the BHA state that the use of any substance affecting blood coagulation is prohibited.

Pharmacognosy (Tease and Evans), the most respected and accurate source of information about the use of medicinal plants, describes coumarins as being a natural component of plants; around 1000 have been isolated. Coumarin itself has been found in around 150 species of plants (including clovers and alfalfa). The coumarin content increases when the plant is cut as a crop (including hay, alfalfa, red clover, and sweet clover).

A chemical called trans-glucosyloxycinnamic acid is converted to coumarin, and conversion also takes place if the plant is damaged (as in the case of hawthorn and horse chestnut during the cutting of a hedge). The aroma of the new-mown crop, which intensifies as drying increases, is an indication that coumarin (benzo-alpha pyrone) is being formed. The highest content of coumarin is contained in sweet clover - which is grown extensively in America and Canada as a hay and forage crop - and red clover, which is found in the UK and is sold as a seed mix suitable for equine pasture. Some plants, such as sunflowers and soya are actually manipulated or engineered to produce more coumarins as this increases the plant’s ability to resist disease.

Whilst coumarins are on the prohibited list, salicylic acid, described in the FEI list as a non- steroidal anti-inflammatory drug, is on the controlled substance list. The medical dictionary describes salicylic acid as a phenolic acid that is used in making pharmaceuticals and dyes, as an antiseptic and disinfectant, especially in the treatment of skin. It is also used as an analgesic and anti-pyretic and in the treatment of rheumatism - better known to us as Aspirin.

Aspirin is made from Acetyl-salicylic acid and was developed in 1853 from willow bark and meadow sweet, which contain a natural ingredient called salicin, a similar chemical compound with similar attributes to Aspirin but possibly without the detrimental gastric side effects. Both salicin (willow and meadow sweet)  and acetylsalicylic acid (aspirin) break down in the body to form salicylic acid and this metabolite is found in the urine, so at this point there are no differences between the synthetic and the natural chemicals. As they leave the body in the urine, they are the same chemical compound.

Salicylic acid is on the controlled medication list of the FEI and is prohibited by the BHA. Meanwhile, meadowsweet has obviously become a very popular choice of additive in anti-inflammatory formulas for horses. This gives rise to some questions.

Important Questions Relating to the FEI/BHA Banned Substance List

  1. Is it accurate to describe salicylic acid as a non-steroidal anti-inflammatory drug (NSAID) as described by the FEI when salicylic acid is the urine metabolite?

  2. If salicylic acid is on the controlled substance list, does this mean that there are threshold limits in urine tests to accommodate the fact that horses grazing may ingest salicin as a common component of native pasture plants and as an additive to many popular feeds and supplements? Or does the term “controlled substance” relate to the prescription and administration of Aspirin (Acetylsalicylic acid)?

  3. Is it acceptable to state on the packaging of formulas containing salicins that they are approved by the FEI, BHA and any other governing body, or should the label explain that the urine metabolite is on the controlled medication list?

  4. Do the companies that include willow and meadow sweet add a standardised extract with a quantifiable amount of salicin? Or, if using the complete herb, do they do separate tests using chromatography to determine and be able to advise people who are involved in top-level competition about the likely levels of salicylic acid in the urine metabolites?

  5. Meadow sweet is also an anticoagulant well known for its interaction with warfarin. Should meadow sweet (salicin, urine metabolite salicylic acid - the same as aspirin) now be included on the prohibited list along with coumarin, as the wording from the FEI is that coumarin is prohibited as an anticoagulant along with any other biological substance with a similar action?

  6. Should coumarin be on the controlled substances list - as salicylic acid is - to allow for the ingestion of the normal feed ration?

Where Does This leave the End User of a Horse Feed or Supplement?

It is a grey area with many pitfalls for the unwary. Many manufacturers state on their labels that their supplements are ‘approved/allowed’ or contain ‘no banned ingredients’ with respect to the BSJA , BHA, BEF and the FEI (a web search revealed 10 in as many minutes). It is important to realise that these governing bodies do not “approve of”, nor state that they “allow” anything, and given the discussion above, “no banned substances” is a very brave statement to make with a multi-ingredient formula.

The end user needs to ask certain things of their supplement manufacturer:

  1. Are they trained in ethnopharmaceuticals? 

  2. Are they able to supply relevant information concerning the ingredients?

  3. What is the evidence that their ingredients are ‘allowed’ from the governing bodies they state? 

  4. Can they provide scientific evidence to back up claims they make?

In most cases the answer will be no. For example, scientific testing can be hugely expensive and well out of the budget of smaller supplement manufacturers. We all know the consequences of a positive test, and the only way you can be sure is through the transparency of the manufacturer you are dealing with and their knowledge. Open and honest dialogue is the key.

I was asked (by the team vet) to give a presentation to a team of riders training for the Olympics. He was concerned that the supplements being brought into the yard might contribute to the horse failing a drug test. Going through the supplements, one rider was surprised to find that a major event sponsor's supplements contained a banned substance. Writing to the manufacturer, he was told the supplement fell within 'allowed levels'.

Does the word banned then mean something else when provided by a major sponsor?!

About EquiBiome

Equibiome uses the latest MiSeq NGS technology to produce a snapshot of the horse’s internal microbial community. The data produced provides horse owners with valuable insight into their horse’s diet, metabolism and energy production, which together contribute to health and performance.

Equibiome is a team of biochemists, equine microbiologists and geneticists. Our aim is to help horse owners better understand equine gut health and to take the guesswork out of what and how to feed their horses. 

We offer a range of equine faecal test kits and Biome Foods. Our Biome Foods are designed to support a healthy equine hind gut biome and can be recommended based on the results of the test.

110 views0 comments


bottom of page