January 31, 2024 (Lexington, KY) – The Horseracing Integrity and Safety Authority (HISA) will fund three scientific studies on the use of furosemide (also known as “Lasix”) on horses during the 48-hour period before the start of a Covered Horserace, including the effect of furosemide on equine health and the integrity of competition. The three projects selected for funding were approved by HISA’s Board of Directors following a recommendation from HISA’s Furosemide Advisory Committee (FAC).

Under the Horseracing Integrity and Safety Act, HISA is required to fund robust and rigorous scientific research on the topic of furosemide to inform the FAC’s future recommendations to the HISA Board on whether and how to amend HISA’s existing furosemide regulations. The HISA Board has approved $773,500 in grant funding for projects to be conducted at Nationwide Children’s Hospital, the University of Florida College of Veterinary Medicine and Washington State University over the next two years.

A request for proposals was issued by HISA in August 2023. Of the proposals submitted, the following were recommended by the FAC and approved for funding by the HISA Board:

Examining Associations Between Furosemide Treatment & Racehorse Health and Welfare

Principal Investigator: Amanda Waller, Bsc, PhD, Research Scientist, Center for Clinical and Translational Research, Nationwide Children’s Hospital

This study will examine the effects of race day furosemide treatment on the health and welfare of Thoroughbreds as well as their long-term racing performance. An analysis will be conducted to assess the association between pre-race furosemide administration and fatal injury, while also comparing the performance metrics – including lifetime earnings, career length, lifetime starts, starts per year, placings and average speed figures – of horses that raced exclusively on furosemide as 2-year-olds and horses that did not receive furosemide for any races during their 2-year-old year.

Effects of Repeated Furosemide Administration on Electrolyte Homeostasis and Bone Density in Healthy Adult Exercising Thoroughbreds

Principal Investigator: SallyAnne L. DeNotta, DVM, PhD, DACVIM., Clinical Assistant Professor, Large Animal Medicine, University of Florida College of Veterinary Medicine

This study will examine the effects of repeated furosemide administration on electrolyte homeostasis, parathyroid response, and urinary electrolyte excretion in exercising adult Thoroughbreds. The study will also examine the effects of repeated administration on bone density and strength using minimally invasive methods of measurement, including DEXA scan and OsteoProbe.

Does Pre-Race Administration of Furosemide to Thoroughbred Racehorses Prolong Their Racing Careers?

Principal Investigator: Warwick Bayly, BVSc, PhD, DACVIM, Professor, Department of Veterinary Clinical Sciences, Washington State University

This study will examine the impact of severe exercise-induced pulmonary hemorrhage (EIPH) on horses’ careers and the health of the racing industry more broadly. In doing so, the study will assess whether regular furosemide treatment is associated with more career starts and greater longevity and the impact of banning furosemide for 2-year-olds on the duration of their careers and number of lifetime starts. The study will also seek to determine the extent to which severe EIPH impacts the number of subsequent race starts, the periods between them and, when applicable, the time between the diagnosis of severe EIPH and retirement.

Researchers will be required to present final reports on their findings to the FAC on or before January 31, 2026.

“The Furosemide Advisory Committee is grateful to the expert researchers who responded to our request for proposals and look forward to partnering with Nationwide Children’s Hospital, the University of Florida College of Veterinary Medicine and Washington State University on this important research,” said FAC Chairman Dr. Scott Palmer, VMD. “The lifelong health and wellbeing of Thoroughbreds is our top priority. This work will help ensure we have policies in place to safeguard these remarkable animals and the integrity of the sport.”