CHRB Eyes Lower Phenylbutazone Threshold

Lower thresholds for the common pain reliever phenylbutazone (Bute) in post-race tests of horses could be on the way in California in spite of objections from horsemen.

At its meeting Feb. 17 at Santa Anita Park in Arcadia, Calif., the California Horse Racing Board (CHRB) approved a 45-day comment period for a rule change that would reduce the permitted level of phenylbutazone from five micrograms per milliliter of blood plasma or serum to two micrograms.

In proposing the reduction, ,Rick Arthur, DVM, CHRB equine medical director, said that the current allowable levels of non-steroidal anti-inflammatory drugs such as phenylbutazone and flunixin (Banamine) could be compromising pre-race examinations by veterinarians checking horses for soundness.

"This is a safety issue," Arthur said.

The rule change would also reduce the allowable level of flunixin from 50 nanograms to 20.

The lower levels would make it easier to detect existing injuries and perhaps prevent catastrophic breakdowns, said Arthur and two other veterinarians who expressed support for the rule change.

Horsemen, however, disagreed.

"We think this is a bad idea," John Sadler, president of the California Thoroughbred Trainers (CTT), told the board. "We do not support it. It has very little support among trainers in the North or the South."

Sadler added, "The horse population is painfully thin. We have a good rule. If we go about making rules like this right now we are in danger of stretching our horses even more than they are now."

Board member Bo Derek said that if more horses are identified as injured and scratched as a result, "That's a good thing."

Other board members reserved comment, although chairman Keith Brackpool noted that by sending the proposed change out for public comment, "Most importantly, this would start the debate."

Carlo Fisco, the CTT's counsel, asked for additional time to compile data on the issue to see if the evidence supports Arthur's position.

"We've talked to people who say the science is not there," Fisco said. "We are trying to fill in the gaps."

Pablo Suarez, representing the Thoroughbred Owners of California, said the organization is on record against the proposed lowering of levels for phenylbutazone but recognizes that national guidelines are changing. He said he was concerned that a reduction in phenylbutazone level could result in more joint injections in horses.

Arthur said most horses, from 85% to 90% during recent meets, test at the lower thresholds anyway.

National racing organizations such as the Racing Medication Testing Consortium, Racing Commissioners International, and the American Association of Equine Practitioners are all recommending the lower level of phenylbutazone, according to a CHRB staff report. As of Jan. 1, 2012, the American Graded Stakes Committee will require races to be run at the lower level in order to maintain grade eligibility, the report said.

Also on the drug front, the CHRB approved a 45-day public comment period for a rule change that would allow the agency to suspend an authorized medication if it appears it is being misused.

Arthur said the American Quarter Horse Association, Los Alamitos Race Course, and the Pacific Quarter Horse Racing Association are considering requesting jurisdictions to prohibit the use of the approved bronchodilator clenbuterol (a medication that is used as a bronchial dilator--which increases lung capacity--and is illegal to administer on race day) in Quarter Horse racing. He said that the CHRB has confiscated illicit forms of the drug from Mexico that are being used for muscle building rather than to aid airway passages.

Originally posted on

About the Author

Jack Shinar

Jack Shinar is a frequent contributor to The Blood-Horse magazine and is part of their Digital Media department.

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