NEW YORK — Rick Dutrow, trainer of Kentucky Derby and Preakness winner Big Brown, is facing a 15-day suspension by Kentucky horse racing officials after another horse he trains exceeded the allowable limit for a drug that increases lung capacity.

Dutrow has 10 days to appeal the suspension said John Veitch, the chief state steward of the Kentucky Horse Racing Authority. Salute the Count tested positive for twice the allowable level of Clenbuterol after finishing second in the Aegon Turf Sprint at Churchill Downs on May 2, one day before Big Brown won the Derby.

Dutrow said he hadn't heard officially from the KHRA on Wednesday morning, but told The Associated Press that he usually files an appeal after being penalized.

Clenbuterol is a respiratory enhancer often used by humans who suffer from asthma. Veitch said it has become popular in horse racing because it can increase lung capacity. It is considered a Class B drug. Though use of the drug is allowed, under Kentucky racing guidelines, it cannot be administered 72 hours before a race.

Dutrow raced four horses during Churchill Downs' spring meet, the last on May 17. He does not currently have any horses at the track said Churchill Downs spokesman Darren Rogers.

The penalty is the first for Dutrow in Kentucky. He will not be fined, though the owner of Salute the Count will have to return $20,000 in purse earnings.