view counter
view counter

Dexa / Betamethasone Study Findings

Published: December 4, 2020 12:19 pm ET

No Comments | Jump to Comments

In a presentation made by Dr. Clara Fenger at the Association of Racing Commissioners International Model Rules Committee Meeting in New Orleans, La., on Thursday (Dec. 3), she described some unexpectedly high serum concentration levels found in experimental horses that were demonstrated to be caused by environmental contamination in the study she submitted as part of her proposal.

As a result, Dr. Fenger, on behalf of the North American Association of Racetrack Veterinarians, who is the sponsor of the proposal, called for “alternative penalties for drug positives that are likely to result from environmental contamination and unlikely to have a relevant effect on the animal. Among the biggest environmental substance offenders are dexamethasone and betamethasone.”

The U.S. Trotting Association, based upon the recommendation of the Harness Racing Medication Consortium and the National Horsemen’s Benevolent & Protective Association, are in support of this proposal.

The usage of Dexamethasone (DXM) done in Dr. Fenger’s research utilized 20 mg administered at 48 and 72 hours out, where measurements were made and studied. From that it appears there is the likelihood of a positive test at a risk of 1 out of 50 from resultant environmental contamination and even more significantly at levels in and of themselves having no pharmacological effect at the current penalty level of 5 pg/mL.

The recommended solution stems from the problem that the current post-race threshold level is set too low at 5 pg/mL of DXM. At this current threshold level, there have been studies by Dr. Soma and others that have found this unexplained high risk of what could be labeled a false positives. The research demonstrated these false DXM positives even where the administration was extended out to 96 hours.

The current rules at this 5 pg/mL level mandate a disqualification, loss of purse and a $10,000 fine.

As a result of this research, Dr. Fenger recommends that the threshold of 5 pg/mL, but no more than 100 pg/mL at 72-hour withdrawal, should trigger a different penalty schedule due to the lack of any pharmacological effect.

Under this proposal, if anywhere from 5 pg/mL up to a 100 pg/mL level is detected in a sample, that a penalty be imposed that would not constitute a drug violation or result in a disqualification, loss of purse and the $10,000 fine.

By this recommendation, in those situations for a first offence between 5 pg/mL but less than 100 pg/mL, there would be a warning; the second violation would generate a small fine; and the third a fine of 10 per cent of the advertised purse.

For example, under this proposal a penalty for a third DXM positive of less than 100 pg/mL in a race with a $1 million purse would result in the reduction of the winner’s share by $100,000.

For any result above the 100pg/mL level, the resultant penalty would remain the same as it currently exists at the 5 pg/mL level, which is a drug violation, disqualification, loss of the total purse and a $10,000 fine.

The proposal was referred to the ARCI’s Drug Testing Standards and Practices Committee for review and recommendation.

To read Dr. Fenger’s complete proposal, click here (see Agenda Item No. 5 on page 28).

To view the summary of Dr. Fenger’s study, click here.

To read Dr. Fenger’s complete study, click here.


view counter

© 2021 Standardbred Canada. All rights reserved. Use of this site signifies your agreement and compliance with the legal disclaimer and privacy policy.

Firefox 3 Best with IE 7 Built with Drupal