Re-evaluation of the regulation of omeprazole in racehorses: An evidence-based approach.

Medication control and doping control have been established in horse racing to ensure the integrity of the sport and the welfare of the horses. This ensures that horses do not compete under the influence of any drugs, including omeprazole, a therapeutic medication used to treat equine gastric ulcer syndrome. In this study, pharmacokinetic data were produced in equine plasma and urine following an oral administration of 4 mg/kg of generic buffered formulation of omeprazole to six Thoroughbred horses in five daily doses to determine an appropriate screening limit and detection time in equine plasma and to assess whether the current detection time of 72 hr in equine urine would be applicable when an alternative omeprazole product is administered. Cmax of 436-2,432 ng/ml and AUC0-tau of 1,476-4,371 ng hr ml-1 were obtained for plasma and indicated, in conjunction with other published oral omeprazole studies, that an appropriate plasma screening limit would be 500 pg/ml with a detection time of 48 hr. Urine analysis showed that omeprazole could be detected for up to 25 hr above the previously established urine screening limit of 500 pg/ml and thus indicated that the detection time advice could be potentially reduced from 72 to 48 hr to allow more comprehensive treatment of gastric lesions.

Detection of prohibited substances in equine hair by ultra-high performance liquid chromatography-triple quadrupole mass spectrometry - application to doping control samples.

The detection of drugs in human hair samples has been performed by laboratories around the world for many years and the matrix is popular in disciplines, such as workplace drug testing. To date, however, hair has not become a routinely utilised matrix in sports drug detection. The analysis of hair samples offers several potential advantages to doping control laboratories, not least of which are the greatly extended detection window and the ease of sample collection and storage. This article describes the development, validation, and utilisation of a sensitive ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC-MS/MS) method for the detection of 50 compounds. This provides significantly improved coverage for those analytes which would be of particular interest if detected in hair, such as anabolic steroid esters and selective androgen receptor modulators (SARMs). Qualitative validation of the method resulted in estimated limits of detection as low as 0.1 pg/mg for the majority of compounds, with all being detected at 2 pg/mg or below. The suitability of the method for the detection of prohibited substances in incurred material was demonstrated by the successful detection of several compounds, such as stanozolol, boldenone undecylenate, clenbuterol, and GW-501516, in genuine equine hair samples. Estimated concentrations of the detected substances ranged from 0.27 to 8.6 pg/mg. The method has been shown to be fit-for-purpose for routine screening of equine hair samples by the analysis of over 400 genuine hair samples.