In an effort to curb overuse of thyroid medications, the California Horse Racing Board has issued new instructions to veterinarians and horsemen for prescribing, dispensing, and labeling thyroid hormones.

The efforts are to ensure that those involved are in compliance with CHRB regulations.

The advisory, issued Monday, points out that all thyroxine within CHRB enclosures must be prescribed by a Board-licensed veterinarian for a specific horse and condition.

In addition, the medication must also be properly labelled in compliance with federal and state laws and CHRB regulations. Horse owners are encouraged to review their veterinary bills and consult with their veterinarians if thyroxine has been prescribed to any of their horses.

The horse, diagnosis, dosage and estimated last administration date must be reported to the CHRB official veterinarian by practicing veterinarians. The administration of thyroxine or thyroid hormones to horses must also be reported by trainers. Any thyroxine or thyroid hormones or thyroid hormone analogs found within the racing enclosure and not properly labelled will be confiscated as contraband.

Thyroxine is prescribed for hypothyroid conditions and to assist weight loss in unusual circumstances.

(CHRB)