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This session, for which I awoke at 4:30 am and drove like a bat out of hell from Phoenix to Tucson in 1-1/2 hrs, and then spent another hour in horrible Tucson traffic getting from I-10 to the Loews Ventana Resort but luckily this thing started late, was billed as "A common sense discussion about the use and testing of therapeutic medications in the racehorse". That is pretty much what it was, a "levelset" for everyone at the Symposium (the hoi polloi) as to what sort of equine conditions get treated at the track and what medications are used to treat the conditions. The real doctors went into seclusion in private sessions after this one public session. It was well worth it. I learned more in 2 hours about medication and testing than I have in 8 years of reading the "just accelerate the molecules" medication experts on the Derby List. :) First presenter was Richard Sams, a PhD of some sort at Ohio State. He started us out with a review of (or introduction to) the terminology of testing, and an excellent introduction to the technology of testing. Interesting items here were the difference between screening tests (thin layer chromatography, immuno-assays) and confirmatory tests, and their costs and difficulties. Excellent description of how the tests work, and what their respective strengths, weaknesses, and costs are. Thin layer chromatography is labor intensive and difficult to automate, but can find new substances on their first use. Immuno-assay can be automated but there has to be a test for a specific drug. Development of a test for a new drug in an immuno-assay can cost $50k. The machines to do some of the confirmatory tests run up to $500k. Various labs do their screening and confirmations differently, some using non-validated methods. Next presenter was Dr. Richard Arthur, a racetrack vet and owner in Southern California. He gave us an overview of the types of healthcare horses will receive before a race. First condition is EIPH, or bleeding. Dr. Arthur made it clear this has been going on forever, as the great grandsire of Eclipse was never raced as he was a bleeder, and even Herod "burst a vessel". Some really icky slides of race horse lungs, plus description of horse lung structure, and discussion of scarring and buildup of iron compounds due to repeated bleeding. Point made here that bronchodilators can only dilate diseased bronchial passages, and won't do a thing for healthy ones. Other conditions to treat were gastric ulcers, and arthritis caused by the pounding and stress of being a professional athlete. Point made about the treatment->withdrawal->performance cycle that's universal, even in "drug-free" racing jurisdictions, and how that impacts on testing and positives. Third presenter was Cynthia Kollias-Baker, DVM and professor of equine pharmacology at UC Davis. Her presentation was on the subject of clenbuterol, and the many misconcepions about it. The drug relaxes constricted airways and enhances the removal of debris (dirt, and other crud) from the airways, perhaps its most beneficial aspect. There is also evidence that it is a weak anabolic agent, building up muscle mass, but anabolic steroids do a much better job of this for cheaper, and the use of these is mostly legal, and a huge dose of clenbuterol is required to achieve the weak effect. Whether there's any synergistic effect to both clenbuterol and steroids is undetermined. Myths abound. Can it make a healthy horse run better? Various studies show no performance enhnacing effects at the normal therapeutic levels. Will it enhance the performance of a horse with respiratory disease? Probably not, as the body already produces substances such as epinephrine under competition conditions, and there are studies that show it it will actually interfere with these. Are low-dose intra-tracheal injections effective? (Very interesting to hear this.) Probably not, as low doses of the drug produce little effect. Clenbuterol is not a "great" bronchodilator. However, there is a window of 30-60 minutes where if an intra-tracheal injection was given followed by a small dose of Lasix, the drug could not be detected. The point was made here this would have to be nearly at the point the horse was in the paddock before a race. This is a matter for security. Third myth is that positive tests equal race day administration. Not likely; it's usually a result of therapy. Clenbuterol is a fat-loving drug that lingers in bidy tissues for up to 30 days. Summary: Probably not a performance enhancing drug, especially at the levels being detected. Fourth presenter was Dr. Warwick Bayly of Washington State University on the subject of Lasix. This drug has effects on a wide variety of tissues, down to the level of blood cells, but there are three primary effects: diuresis, reduced blood pressure in the lungs, and improved breathing and airway functions in horses with Chronic Obstructive Pulmonary Disease. There are also some adverse effects with prolonged use, but none noted for one shot deals in healthy horses not getting other drugs. Is it a performance enhancer? It will produce a 2-4% decrease in body weight, and coincidentally increase the red blood cell and protein concentration in the blood. It also reduces lung blood pressure by about 20%. The effects can be negated by re-introducing fluids (saline, etc) and may be inhibited by NSAID's. What is the relationship between the drug and performance? Studies show an equivocal improvement with Lasix. Horses ran faster, finished better, and won more money. What is the basis of this improvement? Dr. Bayly felt the weight loss was very important. Breathing mechanics were not improved. EIPH prevention was not demonstrated, but the reduction in severity of EIPH incidents (all horses show EIPH to some extent) was possible (64% of horses measured lower). Dr. Bayly said the weight loss was the big issue, however there are lots of unanswered questions, such as does it improve overall health by reducing the severity of the incidents? In summary, Lasix helps some horses but not others, and why is unknown. Final presenter was Dr. Wayne McIlwarith of Colorado State, on the subject of NSAID's and corticosteriods, and we got kind of gypped on this as time was short and he was urged to "cut it short" so what he did was rush through what would otherwise have been an excellent presentation. These are drugs for joint disease, to decrease pain, improve function, and prevent various diseases such as arthritis. Very detailed (but quick) explanation of the mechanisms of cell damage, and discussion of the COX enzymes (NSAID territory) and the other side of the coin which was corticosteroid territory. I'm sorry it went too fast. An interesting revelation was that two racing jurisdictions have no specified limits for blood levels of NSAID's, and I can guess what those two are. NSAID's suppress prostaglandins, which potentiate pain and damage cartilage. There's also side effects, such as kidney damage, and analgesic effects (i.e., we can mask pain that would otherwise protect a horse from damaging itself). The corticosteroids are potent anti-inflammatories, but also can have side effects. Depending on the family of drugs, some cheaper common ones (depo-medrol) can have deleterious side effects, up to others (vetalog) that actually show improvements in cartilage. In summary, and it was hard to tell here as things got so rushed, the deal seemed to be that "NSAID's good as long as not too much was used", and "some corticosteroids good and can actually improve cartilage". What I got out of this whole presentation was a much greater appreciation of how hard all this is to reduce to terms of black and white. Hope the AAEP docs did better in their secret sessions.
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