New Clenbuterol Regulations at Los Alamitos Race Course

The California Horse Racing Board (CHRB) implemented new regulations surrounding the use of the bronchiodilator clenbuterol in Quarter Horse racing at Los Alamitos Race Course, located in Los Alamitos, Calif. The new regulations went into effect on Oct. 14 and were prompted by the increasing use of the substance as a replacement for anabolic steroids.

Clenbuterol is a bronchodilator, and it is used in horses with respiratory problems to relax smooth muscles in the airway, causing the airway to dilate. It also stimulates the activity of the cilia in the trachea, assisting the process of eliminating mucus and microscopic debris.

"The underlying issue is that clenbuterol is a beta-2 agonist and like all drugs in this category has adrenergic (muscle building) effects, especially at higher dosages," explained Rick Arthur, DVM, equine medical director of the CHRB. "Clenbuterol was not being used for the drug's intended purpose, as a bronchodilator to treat small airway disease. Rather, clenbuterol was being used as a replacement for banned anabolic steroids."

According to a memorandum from Arthur, "Effective Oct. 14, 2011, the authorization for the threshold level for clenbuterol will be suspended in Quarter Horse races at Los Alamitos. Clenbuterol will become similar to other drugs not specifically authorized by the California Horse Racing Board, if the lab detects clenbuterol at any level, it will be a violation."

Previously, the CHRB allowed horses 5ug/ml of clenbuterol in urine and 25pg/ml of clenbuterol in blood. With the new regulations, Arthur stressed, clenbuterol is not "banned," per se, and can still be used upon the prescription of a CHRB-licensed veterinarian.

"Only the FDA-approved form of clenbuterol, Ventipulmin Syrup, is allowed to be used to treat lower respiratory disease," the memo read. "Veterinarians prescribing Ventipulmin will be required to provide a specific diagnosis for its use on form CHRB-24 (Veterinary Confidentials). As a muscle builder, a horse on clenbuterol starts losing the muscle mass from the repartitioning effect within days without sustained administration.

"A 30 day withdrawal time should safely avoid any inadvertent positive, provided the clenbuterol is the FDA-approved Ventipulmin form of clenbuterol used at the standard therapeutic 5cc twice a day dose (0.8 micrograms per kilogram twice a day)," the memo continued. "Anyone using a non-FDA-approved form of clenbuterol does so at his or her own risk. As always with withdrawal time recommendations, this ... is not a guarantee, warranty, or assurance that the use of any of these therapeutic medications at the dosage listed will not result in a positive post-race test."

The memorandum noted that the CHRB will continue to use out-of-competition testing to monitor compliance in conjunction with its existing post-race testing program.

About the Author

Erica Larson, News Editor

Erica Larson, news editor, holds a degree in journalism with an external specialty in equine science from Michigan State University in East Lansing. A Massachusetts native, she grew up in the saddle and has dabbled in a variety of disciplines including foxhunting, saddle seat, and mounted games. Currently, Erica competes in eventing with her OTTB, Dorado.

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