Drugs and Medications Corner: The Dangers of Overmedication and Under Diagnosis in the Sport Horse
RELEASE: July 23, 2009
AUTHOR/ADMINISTRATOR: By Dr. A. Kent Allen, DVM
In this day and age, there are many medications available to both human and horses. While some of these medications are quite benign, most of them have varying degrees of side effects. Some of the side effects are relatively minor, while some are rapidly fatal. Recent national events have shown us that we must take great care in what we put in our horses. Obviously, horses can neither tell you where it hurts nor can they tell you what they feel like on a given medication. So, paying attention to what our horses have been diagnosed and medicated with is critical.
The USEF equine drug and medication rule is a rule that has evolved for 30+ years and serves almost 30 breed and discipline organizations. It is, however, a rule that has served us well for a long time, as long as we remember to continually modify it in favor of the horse. The last major modification of the rule was in 1998. The modification involved setting dosage restrictions on all of the medications permitted by the USEF. This was accomplished and has since helped people with correctly medicating their horses. Another proposal that was put forward at the same meeting was not able to be passed at that time. The USEF Veterinary committee put forward a recommendation that the Non-Steroidal Anti-Inflammatory Drug (NSAID) be limited to a single medication. This proposal was ahead of it’s time and had neither the research nor the political will to succeed. Since that time the American Quarter Horse Association has adopted a single NSAID rule and has lived with it successfully for many years. It is certainly time to revisit this proposal within the USEF.
NSAID's (Phenylbutazone, Banamine, Equioxx and others) are the most commonly used medications in the athletic horse. These medications provide us with the ability to treat inflamed joints, readily and easily. They are useful in treating colic conditions. They are the single most useful medication in temporarily treating mild inflammatory conditions in the horse. Similar to the NSAID's available for human usage, they are meant to be taken at reasonable doses for a short period of time. Complications of overmedication can occur when they are taken at too high a dose, too long a period of time, or combined with other medications. The complications of overmedication in the horse include gastric ulcers, deterioration of joints and tendons from masking pain and rupture of the intestine. No single NSAID licensed for use in the horse was ever intended to be used in conjunction with another NSAID.
The research of the last 10 years into NSAID use and pain management has taught us much. We are now aware of the very real danger of masking significant injury in our performance horses with more than one NSAID drug. We are aware that "stacking" NSAID use in some circumstances is similar to doubling the dose. We are aware in the stressed horse even normal doses can cause significant side effects. We are aware of how common gastrointestinal side effects (gastric ulcers, colic, intestinal perforation) are with a single nonsteroidal at elevated doses. We are aware that it is difficult to predict the effect on the horse in combining two non-steroidal drugs. In some cases the drugs are no more effective than a single drug, in other cases they were more powerful than two drugs taken separately and in some cases they mask pain more effectively than very potent morphine-like drugs. We are aware that there will always be a need for more research into this area but on this particular topic the answer seems to be clear.
The question has been raised that if we limit treatment to a single non-steroidal drug will that increase the amount of joint injections being put into our horses? First, it is important to understand that a joint injection properly performed in experienced veterinary hands is the single most effective anti-inflammatory treatment we have for a equine joint. Secondly, there are numerous medications to inject into joints. Often it is hyaluronic acid in combination with a variety of cortisones, or bioregenerative therapies such as IRAP. Some of these medications are extremely safe and all of them will significantly reduce joint inflammation. On the question of “are joint injections going to be overused”, the answer is that is already happening today! In some cases joint injections are being used as treatments in 4, 6 or 8 joints without a diagnosis of joint inflammation ever being established. This is dangerous not only from the standpoint of increasing the number of joint injections in the horse and potential side effects but you may or may not be treating the real problem. Accurate diagnosis, including lameness examination, nerve blocks, joint blocks and diagnostic imaging is the most effective method of determining what the problem is and if the horse needs joint injections. This also has the benefit of reducing the cost to owners as well as the risk to the horse.
A similar question has been raised, will we increase the amount of illicit drugs being administered to our horses by limiting legal treatment to a single non-steroidal drug. The vast majority of horse owners and USEF members would never consider this option. A very small minority of people will attempt this option if they think they can get away with it. The real answer is that this small minority will attempt to cheat, no matter what the legal drug rule is. The best defense against these individuals is to have a highly effective drug and medication research laboratory. The USEF Equine Drug Testing and Research Laboratory is one of the most effective equine drug detection laboratories in the world. It is one of 5 FEI equine reference laboratories in the world. The USEF Equine and Drugs and Medications Program spends hundreds of thousands of dollars every year to stay ahead of illicit drug usage. The program tests up to 17,000 samples a year collected on a random basis and will eventually catch someone using illicit drugs.
So the answer to the question of how do we reduce the amount of overmedication and under diagnosis in our horses, is simple. We revisit the USEF medication rule. We make it simpler for our members to understand and implement. We make it safer for our equine friends because they are counting on us to do the right thing.
ABSENT A DIAGNOSIS
Medicine is poison
Surgery is trauma
Alternative therapy is witchcraft