Peptides are increasingly sold in an unregulated market to clients interested in enhancing their appearance or athletic performance. This raises regulatory challenges, especially for laboratories responsible for maintaining the integrity of sports. The Biological Research Unit at Racing Analytical Services Ltd has developed a high-throughput screen for 30 different performance enhancing peptides based on fully automated SPE and fast LC/MS/MS, capable of detecting peptides in urine or plasma at picoMolar concentrations. A novel feature is the derivatisation of basic peptides for enhanced reversed phase chromatography. To validate the effectiveness of this drug testing strategy, peptide metabolism and excretion have been tested by a variety of in vitro and in vivo models. Combined, this technology not only provides an effective platform for regulating the use of peptide based drugs, but may also prove useful for the development of new peptide or peptidomimetic based pharmaceuticals.