Stewards will brief the Racing Victoria Integrity Council over the recent spate of positives to Ibuprofen.

A number of horses have returned positive swabs on raceday to the non-steroidal anti-inflammatory which is not registered for use on horses in training.

But it has been used on horses in rehabilitation from tendon injuries and problems are believed to be caused by the erratic clearance time from a horse's system.

"The horses that have shown the very prolonged and unpredictable clearances of Ibuprofen had been subjected to exceptionally high doses of Ibuprofen continuously over a period of months as part of tendon injury rehabilitation programs," RV's head veterinarian Dr Brian Stewart said.

"It appears that the parent drug has accumulated in the horses bodies and is being cleared from storage sites very slowly and erratically."

Racing Victoria's executive general manager of Integrity Dayle Brown said the matter would be referred to the RV Integrity Council given the exceptional circumstances associated with the recent incidents.

RV is currently formulating a policy for the management of affected horses.

"We are sensitive to the difficulties currently being faced by owners and trainers of horses which have been administered Ibuprofen," Brown said.

"However, Ibuprofen is a prohibited substance in accordance with the Rules of Racing.

"Racing Victoria's Integrity Council will be fully informed of the situation and any potential management options at its next meeting on 1 February, 2016."

Darren Weir and Clinton McDonald are among the trainers to have had different results on horses.

The Weir-trained Signoff recently returned an irregularity after previously testing negative.