Important Reminder About AQHA Rules Governing Use of Dexamethasone
Testing disciplinary procedures for the new threshold will take effect on July 1, 2026.
Image provided by AQHA.
From AQHA:
Beginning in 2025, AQHA lowered the maximum permitted plasma concentration of dexamethasone from the 2024 threshold of 3.0 nanograms per milliliter to 0.5 nanograms per milliliter.
The AQHA Executive Committee approved this rule change, which was recommended by the AQHA Animal Welfare Commission, in August of 2024.
Dexamethasone is a fast-acting corticosteroid used in horses to manage severe inflammation, allergic reactions (such as hives and insect bites), and respiratory conditions like recurrent airway obstruction (RAO/heaves). It acts by reducing inflammation and suppressing the immune system.
Members are encouraged to review and adhere to these updated guidelines to ensure full compliance. For detailed dosing recommendations and additional context, please refer to Rule VIO405.12, located on Page 48 of the 2026 AQHA Official Handbook of Rules and Regulations.
Additionally, beginning July 1, 2026, the standard protocol for positive drug-testing cases will be implemented for any findings exceeding the updated threshold of 0.5 nanograms per milliliter. All applicable cases will be reviewed and processed in accordance with established procedures.
AQHA appreciates your careful attention to this important update and your ongoing commitment to upholding the highest standards of integrity and equine welfare within the industry.
If you have questions, or for more information about this update, please contact Animal Welfare and Public Policy Coordinator Makaila Hall at mhall@aqha.org or Show Logistics Coordinator Conner Smith at csmith@aqha.org.
