Advice on the Use of Ibuprofen (Including Topically) in Racehorses

Updated: 1 August 2022
Issued: August 2010

The risks involved in the administration of Ibuprofen, including but not limited to oral and topical routes, and the lack of pharmacokinetic information on the drug should be well known to trainers through the publicity associated with positive cases over the years.

Ibuprofen is a non-steroidal anti-inflammatory drug and so is a prohibited substance. It is available in numerous human preparations for oral and topical use. Ibuprofen is not registered for use in horses and limited information is available on its excretion.

Trainers are reminded that it is difficult to make any reliable predictions about the clearance of Ibuprofen from horses based on the information available. This is especially so if multiple doses or exposures to the drug have occurred. Further, as previous cases have highlighted, there is a high risk of contamination in racing stables by the use of Ibuprofen in other horses. It is generally noted that:

(i) Large doses of Ibuprofen may result in more prolonged clearance times than smaller doses.
(ii) Multiple doses or exposures to Ibuprofen may result in more prolonged clearance times than a single dose or exposure.
(iii) Different pharmaceutical preparations of Ibuprofen may have different bioavailability which may result in different clearance times.
(iv) Environmental contamination with ibuprofen may result in horses being contaminated with the drug and cause a positive detection in urine collected from a horse.
(v) Topical administration of a gel formulation of Ibuprofen may result in a prolonged clearance of the drug, probably because the gel persists on the hair which acts as a slow-release reservoir
(vi) Any prohibited substance applied to the skin may persist in urine samples for longer than when administered orally or by injection.

Racing Victoria considers that the only safe way for trainers to avoid contravening the prohibited substance offence rules with Ibuprofen is not to administer Ibuprofen to racehorses (at any time) or allow Ibuprofen in racing stables.

Trainers are advised that an elective non-raceday test should be obtained from any horse treated with Ibuprofen prior to racing.