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Addition of arsenic, hydrocortisone, and mirtazapine to the Schedule of prohibited drugs in the Regulations and clarification of prohibitions regarding zilpaterol hydrochloride

July 7, 2022

The Canadian Pari-Mutuel Agency (CPMA) has made the following changes to the Schedule to the Pari-Mutuel Betting Supervision RegulationsArsenic, Hydrocortisone and Mirtazapine are added to the list, and the current restriction for zilpaterol hydrochloride is broadened to include all zilpaterol preparations. 

Arsenic is considered a performance-altering substance with considerable gastrointestinal toxic effects. Because arsenic is naturally occurring in the environment, horse urine contains low levels of arsenic. This amendment will add arsenic to section 2 of the Schedule, and adopt the international threshold of 300ng/mL in urine to control the use of arsenic in Canadian race horses. The CPMA recommends discontinuing the use of all supplements containing arsenic at least 48 hours before a race.

Hydrocortisone is a potent steroidal anti-inflammatory. It is used to treat allergies and other inflammatory conditions. It will be added to section 1 of the Schedule. Synthetic hydrocortisone will be regulated through the detection of hydrocortisone esters in blood and urine.

No. horsesProductDose /RouteAdministrationEG
4Solu-Cortef250 mg IVsingle48 h
4Cortavance152 µg TOPsingle24 h

Mirtazapine is an antidepressant used to treat a wide range of conditions, from behavioral problems to loss of appetite in cats. The addition of this substance to section 1 of the Schedule is consistent with the current approach for other antidepressants.

Zilpaterol hydrochloride is currently listed in section 1 of the Schedule. This amendment will remove the word “hydrochloride”, and clarify that any zilpaterol preparation, metabolite, derivative, isomer and salt should not be present in the sample.

Any detection of the above drugs may result in a positive test.

The CPMA strongly recommends consulting a veterinarian on any decision to administer supplements or medications to a racehorse.

Testing for these drugs will begin on August 1st, 2022.