The Turf Club is to significantly enhance its drug-testing regime from next January.
The announcement comes just a week after Irish racing was rocked by the news that trainer Philip Fenton faces court charges over the alleged possession of banned animal remedies, including steroids.
From next year all horses whether returned in or out of training, or for whom a hunter certificate has been issued after that date, will be liable for testing at any time.
This is just one of a number of measures announced by the Turf Club, all of which are aimed at strengthening its existing drug-testing procedures.
The Turf Club's chief executive Denis Egan said: "While the Turf Club already has an extensive and successful drug testing regime in place, it is an area that is under constant review and where we would never be complacent.
"In 2013 the Turf Club tested 3,207 samples, out of which three were found to be positive. All winners on the racecourse are tested for prohibited substances while Turf Club Veterinary Officers also visit trainers' yards and take samples from horses in training.
"The Turf Club will continue to work with its scientific experts in developing hair testing methodology with a view to its introduction when appropriate.
"All licensees will be required on an annual basis to disclose, as part of their licence application, if they are under investigation for any matter which may influence the granting of a licence. In addition, they will be asked to confirm that substances that are prohibited at all times have not been used by them.
"Clear indications of support have been given by Horse Racing Ireland in relation to providing funding to meet the Turf Club's needs in this important area.
"The Turf Club fully endorses the position announced by the International Federation of Horseracing Authorities in October 2013 that anabolic steroids have no place in horse racing and that they should not be permitted in or out of competition. The Turf Club will be pursuing every means to make this a reality in conjunction with our colleagues in other racing jurisdictions.
"The Turf Club will use every resource at its disposal to ensure that Irish racing is kept as clean as possible and free from drugs.
"Recent developments have pointed for the need to extend the drug testing regime, particularly into the area where horses are out of training, and also to seek new powers to enable the Turf Club veterinary officers inspect premises for illegal drugs".