Gary Lavin Letter to the Editor

The proposal made by a group of trainers at Saratoga to race two-year-olds in 2015 without furosemide is a strong and positive statement to initiate a study to resolve the furosemide controversy once and for all. I would propose a post-race endoscopic study with photographs after actual races to be graded by a blinded jury of experienced practitioners and researchers. The numbers necessary to be statistically significant to be determined by veteran epidemiologists. With the cooperation of owners and trainers, all horses of all ages, sexes, distances, talent levels, raced with or without furosemide could be graded and a final determination of severity determined. 

The accepted grades of zero to four would be used and the number in the study large enough to be irrefutable. EIPH is a natural phenomenon of stressful exercise including all breeds, ages and sexes. Its presence does not necessarily affect the outcome of the competition but it most certainly can. The percentage and severity can vary with environmental and weather conditions but can occur in ideal situations. The occurrence in any individual need not be consistent, but is certainly possible. The numbers are much smaller than generally believed by the racing population. 

We know furosemide reduces EIPH, but cannot prevent it. We need to know the proper procedure for furosemide dosage, route, and timing of treatments for a successful result.

The results of some important studies – 

An Australian study involved 744 horses racing WITHOUT furosemide examined endoscopically over a period of two months, then followed through their entire career. Using the accepted grades of 0 to 4, the results found 13 grade 4 horses. The grade 0 is a finding of total absence of blood, grades 1 and 2 being considered minimal without consequence, and grade 3 being somewhat suspect, but not totally so. The 13 grade 4 constituted 1.6% of the subjects that demonstrated a sufficient amount of blood to possibly affect the performance, possibly affect because horses were examined 45 – 90 minutes post race and could have reached a level 4 after exercise. Six horses demonstrated epistaxis, that being visible blood at the nostril. Endoscopic exam of epistaxis revealed 5 horses to be grade 4, while 1 horse graded a 2. Obviously, epistaxis can not be the only criteria for determining the level of EIPH to affect racing.

A most interesting finding in this study, which included some horses racing until the age of 10, was that grades 0 to 3 raced successfully at their expected level while the grade 4 horses were decidedly handicapped and failed to complete an acceptable career. Mindful that these careers were achieved without raceday medication.

A South African study examined 155 horses racing WITH furosemide and again a week or more later WITHOUT furosemide. 155 horses resulted in 3.4% grade 4 EIPH without furosemide and a reduction of at least one grade in all horses when treated with furosemide.

In Hong Kong, furosemide is not permitted in racing or training. In a very monitored sport, 17,497 starters were found to include 109 bleeders by Hong Kong definition; i.e. epistaxis. That equates to 0.6%. A first offense draws a 3-month suspension for the horse, a second episode results in a lifetime ban. Most interestingly, 30% of first-time bleeders will have a second occurrence sometime in its career. That, of course, means 70% never demonstrated epistaxis again.

Furosemide was introduced into veterinary medicine in the late ’60s and as recently as 1992 when 5 horses raced with furosemide in the Kentucky Derby (the winner not included), it was given sparingly. Then a significant occurrence was noticed by the handicappers in the industry, that horses racing for the first time (after racing enough to establish a pattern) would improve their performance considerably, when racing with furosemide for the first time. Gamblers had found their Paradise. As this phenomenon spread, the result became apparent that furosemide was certainly beneficial the first time and remained fairly consistent thereafter. Research found upwards of 80% or more horses showed signs of what we considered EIPH at some point in their career. The reaction was immediate and overwhelming given the limited knowledge we had at the time. Fast forward to the present day where we find first time starting 2-year-olds racing with furosemide. In the world of horse racing we find ourselves as Mom saw Johnny in the parade: “Everybody is out of step but my Johnny.” The rest of the world seems to be getting along just fine without raceday furosemide.

Outside the United States, racing is conducted without race day medication and the governing bodies see no reason to change. These judicial bodies, usually with a national mandate, announce their decisions and the penalties for infractions can be career-threatening. Appeals and reviews are rarely conducted. 

Obviously, the rest of the world does not look at EIPH the same way America does. Their horses could not be so blessed as to not suffer, to some degree, the same injuries and affectations (bleeding) as we do. The realization, of course, is that medications can and are used in an efficacious manner in adherence to withdrawal times mandated by their authorities. It works elsewhere, or so it seems.

In light of the most recent studies, we may have overreacted.

Some history, in the early days (late ’60’s, ’70’s) a small number of horses were treated with furosemide and the urine samples from some proved difficult to analyze because the furosemide was given so close to the race as to render the sample untestable. Chemists requested a 3-hour cutoff for administration. Keene Daingerfield, the Kentucky Senior Steward, utilized a veterinary committee for such matters. The veterinarians were not only agreeable but suggested a 4-hour time frame to assure the sample quality. Henceforth, the 4 hour, 5cc volume was implemented in almost all states (one state used 3 hours and 10cc with no apparent problem).

Interestingly, in those early days it was not unusual for a horse to receive its furosemide at all times during the day, depending on the arrival of the vet. A horse stabled close to the entrance gate could get its furosemide early in the morning even with a race scheduled late in the afternoon. The horse stabled in a distant barn might have its furosemide late in the morning and be scheduled to race soon after lunch. It seemed to make no difference whatsoever.

Researchers and chemists determined that furosemide has a half-life of 1 hour, which means its peak effectiveness in eliminating fluids from the body is reached in one hour, tapering off over the next few hours. The resulting urine excreted is the result of the kidney “pulling” mostly water from plasma. The plasma is quickly replenished by extra cellular fluid, mainly from the intestines and the lungs. In a very easy trial, a horse can have a blood sample taken at the time of furosemide administration, travel to the track, race and return to its stable. A blood sample taken the next morning will be nearly identical to the pre-treatment sample. Furosemide, obviously, is not overly taxing physiologically. That extra cellular fluid is simply that – extra.

With good husbandry and a healthy subject, the amount of necessary replacement is done in a timely and natural fashion. What is that time period in human medicine? A patient can receive furosemide daily for an indefinite period without alarming concern consistent with sensible monitoring. The frequency can be as varied as multiple doses a day to as little as ONCE A WEEK. 

Furosemide is the 4th-largest prescription medication for human purposes. Our racehorses would parallel humans as teenagers through perhaps their late 30s. Our patient is healthy and sound for racing. EIPH very seldom results in a bacterial infection and viruses are almost never found.

Early research used dosages of 4cc (200mg) to as many as 40cc (2000mg) without untoward effect. Obviously, the safety of furosemide is remarkable.

These studies, scientifically and anecdotally, would certainly imply that furosemide is very safe and that it might be able to be used in a program that would adhere to the rules used internationally. In some foreign countries, a withdrawal time for furosemide has been established. This could certainly be thought that furosemide is indeed used for training and apparently with a regimen that is effective for alleviating EIPH.