Get helpful information for navigating the crowded field of performance-horse medications

Got a headache? You probably pop a pain reliever. That achy knee bothering you today? Perhaps you reach for a non-steroidal anti-inflammatory drug (NSAID). While you might not give your own remedies much thought, you’d better do your due diligence when it comes to your horse’s aches and pains, particularly if you plan to compete. 

Our national governing body (NGB) for equestrian sport, the United States Equestrian Federation (USEF), is responsible for ensuring a level playing field is maintained at its recognized competitions. That means running a tight ship and enforcing rules pertaining to what substances owners, trainers, or veterinarians may and may not administer to horses. 

Generally speaking, two rules of thumb apply to the worlds of equine medications and competition. The first is that, just as in human medicine, new drugs and other purportedly beneficial substances (“nutraceuticals” and the like) continue to be developed. All this innovation keeps the USEF drugs-and-meds folks busy trying to figure out what the new stuff does; how it might interact with other substances; and whether it should be permitted, restricted, or banned in licensed competition.

The second is that, unfortunately, there always seem to be competitors bent on skirting the rules in order to gain an unfair advantage or, perhaps, show a horse that’s not sound. 

The racing industry has gotten plenty of bad press for the drugging of racehorses. In December 2012, the sport-horse world got a taste of the same medicine when The New York Times ran a story about a hunter pony that collapsed and died at the 2012 Devon Horse Show, in Pennsylvania, after having received 15 separate injections of various substances in the three days preceding his death. 

You might not be giving several meds simultaneously. Or you might not dream of giving a horse cocaine or LSD; but somebody’s undoubtedly tried it, for both are on the tiny-type list of USEF forbidden substances, along with about 200 others—and they’re just listed as “examples.” So one of our NGB’s main roles is conducting drug tests at horse shows and imposing penalties on offenders.

With the guidance of Stephen Schumacher, DVM, head of the USEF Equine Drugs and Medications Program, we’ll introduce you to the major categories of performance-horse meds and other substances—what they are and what they do. Then we’ll offer tips for navigating the minefield of substances that could get your horse eliminated from competition.

To Reduce Pain

A dizzying array of substances serve to make horses feel better by helping eliminate pain, inflammation, or both.

Painkillers such as tramadol, a USEF forbidden substance, might have therapeutic value, but they shouldn’t be used in competition because they hide a horse’s pain or unsoundness. 

Corticosteroids are potent anti-inflammatories and immunosuppressants. Dexamethasone (Azium) is a common equine veterinary corticosteroid administered to reduce pain and inflammation and to quell allergic reactions, among others. It’s on the USEF list of medications whose administration and dosage are restricted. 

Corticosteroids are not the same as anabolic steroids, the performance-enhancing “doping” steroids typically associated with bodybuilders and other athletes. Anabolic steroids, which include the male hormone testosterone, are forbidden in USEF competition.

The NSAIDs, as their name suggests, reduce inflammation (thereby offering pain relief) without the use of steroids, which is appealing because long-term steroid use can be harmful. But NSAIDs can have their own drawbacks; one of the best-known NSAIDs, phenylbutazone (“Bute”), can cause ulcers or other gastrointestinal problems, especially if administered regularly. Newer NSAIDs designed to avoid this side effect include firocoxib (Equioxx) and diclofenac (Surpass, a topical cream). And some NSAIDs, such as flunixin meglumine (Banamine), are commonly administered in a single application, such as to relieve colic pain. 

Other drugs use different modes of action to provide pain relief. Methocarbamol (Robaxin), for instance, is a muscle relaxant. Veterinarians sometimes administer this drug to relieve muscle spasms and tightening in horses with sore backs. 

To Calm

This wide category encompasses tranquilizers (acepromazine, reserpine, etc.) and the many “calming” supplements. 

Particularly when having a quiet horse is a competitive advantage, some exhibitors are tempted to resort to artificial means of calming their charges. Most know that sedatives and tranquilizers are forbidden, but some fall into the trap of thinking that a nutraceutical advertised as “natural” or “herbal” is therefore competition-legal. Surprise, surprise: Some herbs that have distinct calming or anti-anxiety properties are the very substances that make up some of the prohibited sedatives and tranquilizers on the market. Most of these herbs—even independent of compounds—are not permitted in USEF competition.

An inhibitory neurotransmitter called gamma aminobutyric acid (GABA, the active ingredient in the supplement Carolina Gold) joined the USEF banned-substances list in 2012. Thought to have calming properties, GABA is worrisome because its injection can cause such side effects as severe shaking and near-collapse, explains Schumacher.

A substance that’s even scarier than GABA, he says, is injectable magnesium sulfate. (Yes, the same active ingredient as in drugstore Epsom salts.) Given intravenously, “vitamin M,” as some users slyly call it, has a calming effect—but it can also kill the horse if administered too quickly. 

Other Effects

We don’t hear about competitors’ wanting to pep up their horses for the arena as much as calm them, but some must want to; otherwise, such substances as methamphetamine and caffeine wouldn’t need to be on the USEF’s forbidden list.

And the rest? Name a drug—legal or illegal—or an herb that we haven’t already covered, and chances are it has some sort of physiological effect that’s disallowed in competition. Tetrahydrocannabinol, or THC, the active ingredient in marijuana? Banned. Guafenisin, the active ingredient in Mucinex and some cough remedies? Banned. Strychnine, aka rat poison? (Ew!) Banned. And the list goes on and on.

A curious subset of the “performance-enhancing” category comprises substances that increase skin sensitivity. Many of the related offenses have occurred in jumpers, which are penalized for knocking down rails. Heighten the sensitivity of the horse’s legs, the thinking goes, and it will hurt more to hit a rail. A number of jumpers at the 2008 Olympic Games were eliminated when they tested positive for capsaicin, an irritant as well as the ingredient that makes hot peppers hot. 

Finally—although we’ve by no means listed every possible substance or its effect—bronchodilators and other similar drugs used to relieve the signs of asthma and other respiratory ailments are also on the banned list because they enhance horses’ aerobic capacity.

Supplements: Use with Caution

Equine nutraceuticals are not regulated by the U.S. Food and Drug Administration. As a result, manufacturers are not required to disclose all ingredients and ingredient levels, and amounts might vary from batch to batch.

What this means for horse show exhibitors is that they might not know for sure whether supplements will cause their horses to test positive for substances forbidden or controlled by the USEF, the latter being drugs that are permitted but only in limited amounts. Veterinarians warn horse owners not to trust product labels that promise otherwise.

If you must feed your horse a nutraceutical and you wish to show in USEF-licensed competition, you’re best off choosing a product whose manufacturer is a member of the National Animal Supplement Council (, says Schumacher. Members of NASC agree to follow quality manufacturing standards, submit to product and ingredient audits, and follow established labeling protocols. In other words, what’s on the label is in the product, with a lesser chance of “surprise” ingredients (but keep in mind that even some of the labeled ingredients might be banned or controlled). For more information on supplement regulation, as well as the role of the NASC, see the August issue.

For the AQHA or FEI Competitor

The American Quarter Horse Association follows most United States Equestrian Federation rules regarding forbidden substances in competition. However, the AQHA’s dosage and time-frame rules for what it terms “conditionally permitted therapeutic medications” (rule VIO405 in the AQHA Official Handbook) differ somewhat from the USEF’s.

The AQHA permits the administration of 13 substances within 24 hours of showing. Among them are several NSAIDs and dexamethasone, as in the USEF rules. But the AQHA permits three substances that are banned in USEF competition: acetazolamide, a drug given to horses testing positive for the disease hyperkalemic periodic paralysis (HYPP); furosemide (Lasix), a blood thinner; and the anesthetics lidocaine/mepivicaine (permitted only when used under specific circumstances). Consult the AQHA ( for more details.

Those elite equestrians who show in FEI-recognized competitions must follow the organization’s stringent anti-doping rules, for both equine and human athletes. See the FEI’s list of banned substances and learn more at

Jennifer O. Bryant

How to Pass a Drug Test

When you enter a horse in a USEF-licensed competition, your signature on the entry form constitutes agreement to abide by the drugs-and-meds rules, which includes consent to equine drug testing. The check you write incorporates a fee (currently $8) that funds the USEF Equine Drugs and Medications Program.

If a horse’s blood or urine sample is found to contain a forbidden substance, penalties vary but usually include forfeiture of any ribbons, trophies, points, standings, and prize money earned at the show; a monetary fine; and public shaming in the form of a penalty notice in the USEF’s member magazine, Equestrian. The horse cannot compete in future USEF shows until all assessed fines are paid.

You don’t want this to happen to you, of course, and you might assume you’re okay as long as you steer clear of those forbidden substances. Unfortunately, it’s not that simple. Even well-meaning competitors get snagged in the drug-testing net because they don’t understand that there are controlled substances and how the USEF approaches these.

Recognizing that some medications have genuine therapeutic value—such as many NSAIDs, dexamethasone, and methocarbamol—the USEF permits their administration but recommends they not be given within certain time frames prior to competition, so as to help ensure that detectable amounts will be below allowed limits. Further, no more than one permitted NSAID can be administered at a time.

Here’s where you need to get out your reading glasses, for there’s a lot of fine print as to the specifics of the allowed dosage amounts and time frames. The USEF publishes a booklet, Guidelines for Drugs and Medications, which contains the text of USEF General Rule (GR) 410. In its 33 pages you’ll find a quick reference guide to the quantitatively restricted meds, followed by several pages of detailed specifics. It’s dense reading, but if you give your horse anything other than hay and feed, you’d better bone up before you show.

You can download the USEF 2013 Guidelines for Drugs and Medications at (click on Rules & Regulation, Drugs & Medications, then select 2013 Guidelines from the menu bar at right). Save the PDF to your smartphone or tablet, or print it out and keep it with you at the barn and when traveling to shows. 

The Drugs & Medications section of the USEF website also contains other helpful links, such as an NSAIDs FAQ and a link to the Fédération Equestre International (FEI) drug rules and the current list of FEI banned substances.

It’s always a good idea to consult your veterinarian well in advance of a show regarding any medications or supplements you give your horse. Be aware, however, that the person who signs the “trainer” blank on the USEF entry form is the “person responsible” for the horse, according to USEF rules. In other words, “My vet gave me incorrect advice” isn’t defensible. If you have questions about the USEF D&M rules, call the USEF D&M Department at 800/633-2472.

Read about managing editor Alexandra Beckstett’s own horse show drug test tips and experiences in “What’s in Your Horse’s Urine Sample?” at

These Substances Are Okay

You might have noticed that we haven’t mentioned some commonly used substances, such as injectable polysulfated glycosaminoglycan (GAG, Adequan), in our lists of banned or controlled substances in USEF-licensed competition. 

Forbidden substances generally have a certain amount of “masking” action or affect horses’ brain chemistry. In contrast, the GAGs and hyaluronate sodium (Legend) act—and this is a gross oversimplification—by helping arthritic joints heal themselves. Therefore, they are permissible in USEF competition.

Another substance that is USEF competition-legal is altrenogest (Regu-Mate, or the generic Altresyn), which suppresses mares’ estrous (heat) cycles. Some mares become erratic and difficult to manage when they are cycling as a result of pain and hormone swings. (Note, however, that there are many “moody mare” nutraceuticals whose ingredients might or might not “test,” so use these with caution.)

The Goal: Fair, Humane Competition

Veterinarians will be the first to tell you that no substance can substitute for correct training. Likewise, seasoned competitors are quick to point out that horses are not automatons, and that judges who reward “dead,” robotic performances are unwittingly propping up competitors’ use of methods to render horses unusually quiet. 

In light of recent negative publicity, it is likely that drugs-and-medications rules will only become more stringent. New medications might hold promise for enhancing horses’ health and welfare, but with their availability comes the responsibility to use them correctly and never to compromise one’s horsemanship or sportsmanship standards for the sake of a ribbon.