Use of Calming Agent in Racehorses Examined

The horse racing industry is taking a closer look at a relaxant that produces optimum results when administered within a few hours of a race.

The drug, gamma-aminobutyric acid (or GABA), was banned by the United States Equestrian Federation (USEF) in 2012. The substance, a supplement also known as "Carolina Gold," was found by USEF research to have "many adverse reactions" in horses.

GABA is an amino acid natural to a horse's system. At higher levels it has a calming effect that can conserve a horse's energy prior to a race.

Attorney Alan Foreman, chairman of the Thoroughbred Horsemen's Association who has experience in USEF drug cases, said March 27 if too much GABA is administered, "a horse will drop." He said the substance must be administered intravenously.

Racing industry officials are looking into reports that GABA is being administered on race day along with furosemide—the anti-bleeding medication also called Salix or Lasix—or adjunct bleeder medications in states in which private veterinarians administer race-day shots. GABA's effects generally are gone in three to four hours, and furosemide, in most racing jurisdictions, is administered within four hours of a race.

Though there is a test for GABA, not all laboratories test for it. Officials said that in Kentucky, an October 2012 rule that allows only regulatory veterinarians to administer race-day furosemide appears to have curtailed GABA use.

"I saw some evidence to suggest it was being used in Kentucky," said Mary Scollay, DVM, equine medical director for the Kentucky Horse Racing Commission.

Regulatory administration of race-day furosemide is a key component of model drug reform measures; major racing jurisdictions have adopted the policy or are in the process of doing so.

"Getting vets out of the stalls on race day is one way to combat its use," said Ed Martin, president of the Association of Racing Commissioners International (RCI).

Foreman and Scollay said from a testing perspective, the difficulty comes in establishing the normal level of the amino acid in a horse, and then setting an accurate threshold level.

"The drug is eliminated (from a horse's system) rather quickly, so it may be difficult to detect an administration made at four hours," Scollay said.

Rick Sams, PhD, director of the HFL Sports Science Laboratory in Lexington, said March 28 that research performed by George Maylin, DVM, PhD, at Cornell University and Tom Lomangino at the USEF testing laboratory produced different results. Maylin tested for GABA in New York-based racehorses, while Lomangino tested for the drug in samples taken from pleasure horses.

The levels of the amino acid were substantially lower in the pleasure horses.

"Was that due to treatment (administration of GABA in racehorses) or because there were methodological differences in the testing?" said Sams, who agreed with Scollay and Foreman that establishing the naturally occurring level in a horse is the primary challenge to testing.

When asked if furosemide can interfere with testing for GABA, Scollay said she hadn't heard that was an issue. Sams concurred, noting that GABA is tested for in plasma, and blood concentrations aren't affected by furosemide.

GABA doesn't specifically appear in the Uniform Classification Guidelines for Foreign substances, though as a depressant it can affect a horse's performance. Under RCI guidelines, "found substances or drugs not included should be treated as Class 1 violations warranting Class A penalties" unless otherwise advised by consultation with RCI and the Racing Medication and Testing Consortium.

The RMTC is in the process of devising a course of action regarding GABA and other substances, officials said.

Originally published on

About the Author

Tom LaMarra

Tom LaMarra, a native of New Jersey and graduate of Rutgers University, has been news editor at The Blood-Horse since 1998. After graduation he worked at newspapers in New Jersey and Pennsylvania as an editor and reporter with a focus on municipal government and politics. He also worked at Daily Racing Form and Thoroughbred Times before joining The Blood-Horse. LaMarra, who has lived in Lexington since 1994, has won various writing awards and was recognized with the Old Hilltop Award for outstanding coverage of the horse racing industry. He likes to spend some of his spare time handicapping races.

Stay on top of the most recent Horse Health news with FREE weekly newsletters from Learn More