Opiates are widely used in the management of pain and thus, can be abused leading to drug dependency.Their use in the management of pain has also lead to abuse in an attempt to allow the athlete, whether human or horse, to compete despite unsuitable physical conditions.A horse competing under these conditions is especially dangerous for the equine athlete and the jockey or driver.A horse tumbling to the ground while running in excess of 35 mph can be devastating to both the horse and human participant.The most troubling part is that these agents have been illegally administered to horses to alter their performance.To deter such illegal use of opiates in racehorses, sensitive methods for screening and confirmation of these agents are essential.A method to address this need is the use of capillary electrophoresis (CE) coupled with tandem mass spectrometry (MS).