PDFWAC 260-40-280
Impaired horses.
An owner or trainer may not enter or start a horse that:
(1) Is not in physically sound and competitive racing condition.
(2) Has been trachea-tubed.
(3) Has been nerved except as provided in (a) and (b) of this subsection.
(a) Horses that have had a digital neurectomy (heel nerves) may be permitted to race subject to the prerace veterinary examination.
(b) Horses that have been nerved, blocked with alcohol or any other medical drug that desensitizes the nerves above the ankle will not be permitted to race.
(4) Has impaired eyesight in both eyes.
(5) Has been treated by extracorporeal shock wave therapy or radial pulse wave therapy other than allowed in WAC 260-70-545(4).