The use of Lasix (furosemide) has come under scrutiny in the racing industry with some analysts arguing that the use of the drug is one of the reasons why we’ve gone so long without a Triple Crown winner.
Lasix is injected to prevent bleeding – Exercise Induced Pulmonary Hemorrhaging. The argument is that almost all horses bleed at some point and that Lasix can help prevent it by lowering a horse’s blood pressure. According to a post on Bits n’Bunny:
In every horse’s lungs, there are blood vessels that end in air-sacs called alveoli. The alveolus are enclosed by capillaries, a tiny group of blood vessels about one percent of the thickness of a human hair. On average, one horse alone has approximately three hundred billion capillaries. When these capillaries burst under pressure, bleeding in the lungs ensues.
Although racing officials in the US don’t consider it to be a performance-enhancing drug, the US and Canada are the only two major racing countries where race-day injections of Lasix are legal.
And the use of Lasix is ubiquitous. According to this article in the Courier-Journal:
The last horse to win the Derby without Lasix was Grindstone in 1996. From that Derby through last year, only 13 of 292 Derby starters raced without Lasix, or roughly 4 percent.
The downside to Lasix is that it dehydrates horses. For horses that are already stressed by prepping for the Derby and then the Preakness, the added dehydration may make it almost impossible for a horse to run well in three big races over five weeks.
In the 1970s there were three Triple Crown winners: Secretariat (1973), Seattle Slew (1978) and Affirmed (1979). Lasix was first introduced in the mid-70s and since then, there have been no winners. Coincidence? Sportswriter Bill Finely believes that Lasix is an obstacle to winning the Triple Crown.
Some vets believe that Lasix is a short cut taken by trainers who don’t condition properly:
“Bleeding in a race is reflective of inadequate care and preparation, of miscalculations and untoward medication practices. Lasix perpetuates substandard horsemanship, artificially suppressing the untoward result (bleeding) of inadequate preparation of the thoroughbred,” says Vet Sid Gustafson in an article in the Paulick Report.
What do you think?