The Rules are based upon participation free of prohibited substances and, therefore, all racehorses in Hong Kong are tested pre-race for such substances. Selected horses will also be tested post-race.

2. The Rules provide that "The Stewards shall have the power to withdraw at their discretion any declared runner if a pre-race test taken from such horse is reported by the Chief Racing Chemist or other chemist authorised by him as positive or potentially positive for the presence of any prohibited substance."
3. The Trainer may also be punished for breaching the Rules, in the event that a horse which has been declared to start in a race, is found to have been administered or been exposed to a prohibited substance.
4. Whilst in Hong Kong no treatment of any sort may be given to any racehorse without prior permission from the Club's veterinary surgeons who are the only persons authorised to administer all treatments.  If in doubt about treatment of any sort, the horse's Trainer, or his authorised representative should contact one of the Club's veterinary surgeons.  There are many specific Rules and Instructions concerning treatment of racehorses in Hong Kong and you should be aware that on the day it is to race, no horse shall receive any treatment which includes any injection, any form of inhalation therapy or nasogastric intubation.  Also, intra-articular injections are not permitted within two (2) clear days of racing, where a clear day does not include the day of administration or the day of the race.  This applies to the procedure itself and not the medications used, which may well have longer pre-race restrictions applied. No horse is permitted to be subject to a endoscopic examination on the day on which it is to race until after having competed in its race without the express approval of Executive Manager of the Department of Veterinary Regulation. The use of ice, ice packs or cold water treatment on a horse's limbs within two (2) hours of the scheduled time of the race is strictly prohibited.
5. It must be noted that any person providing veterinary services in Hong Kong must, as a statutory requirement, under the Veterinary Surgeons Registration Ordinance, be registered with the Veterinary Surgeons Board of Hong Kong. To obtain such registration may take several weeks. Should a horse's connections anticipate that they may require the services of their own, or a specialist veterinary surgeon, then application to the Veterinary Surgeons Board of Hong Kong must be made at least four (4) weeks prior to such services being required.
6. It should be emphasised that all treatments given to, or procedures carried out on, a horse by a visiting veterinary surgeon, who has been properly registered in Hong Kong, shall be supervised by a Club veterinary surgeon.

The prohibited substances under the Club's Rules are:

a)  Substances capable at any time of causing an action or effect, or both an action and effect, within one or more of the following mammalian body systems:

  • the nervous system
  • the cardiovascular system
  • the respiratory system
  • the digestive system
  • the urinary system
  • the reproductive system
  • the musculoskeletal system
  • the blood system
  • the immune system except for licensed vaccines against infectious agents
  • the endocrine system
b) Endocrine secretions and their synthetic counterparts

c) Masking agents

d) Oxygen carriers

e) Agents that directly or indirectly affect or manipulate gene express.

Prohibited substances below the following thresholds are not actionable:

Threshold name Threshold
  • 0.3 microgram total arsenic per millilitre in urine
  • Boldenone
  • 0.015 microgram free and conjugated boldenone per millilitre      in urine from male horses (other than geldings)
  • Carbon dioxide
  • 36 millimoles available carbon dioxide per litre in plasma
  • Dimethyl sulphoxide
  • 15 micrograms dimethyl sulphoxide per millilitre in urine, or
  • 1 microgram dimethyl sulphoxide per millilitre in plasma
  • Estranediol in male horses (other than geldings)
  • 0.045 microgram free and glucuroconjugated 5a-estrane-3b, 17a-diol per millilitre in urine.
  • Hydrocortisone
  • 1 microgram hydrocortisone per millilitre in urine
  • Methoxytyramine
  • 4 micrograms free and conjugated 3-methoxytyramine per      millilitre in urine
  • Salicylic acid
  • 750 micrograms salicylic acid per millilitre in urine, or
  • 6.5 micrograms salicylic acid per millilitre in plasma
  • Testosterone
  • 0.02 microgram free and conjugated testosterone per millilitre      in urine from geldings, or
  • 0.055 microgram free and conjugated testosterone per      millilitre in urine from fillies and mares (unless in foal)
  • Theobromine
  • 2 micrograms theobromine per millilitre in urine
  • The conjugated substance is the substance that can be liberated from conjugates.