treatment. In pilot clinical trials with ractopamine, four patients showed little evidence for central nervous system stimulation. Whether long-term treatment with these drugs results in the development of tolerance to these adverse effects is unclear. Analytical method for residues in livestock In cattle and swine tissue, it was found in 2007 that a procedure for the analysis of ractopamine residues in liver or muscle can be performed by high performance liquid chromatography (HPLC) with fluorescence detection. The confirmatory method include reversed-phase HPLC/electrospray ionization triple tandem quadrupole mass spectrometry. The limit of quantification of the drug using this LC/MS instrument was shown to be 1 ng/g (1 ppb). In cattle, a 2018 Chinese study promoted the use of hair as an indelible test of feed containing ractopamine. In popular culture Stuntman and comedian Steve-O has publicly spoken of his involvement as a test subject in an early ractopamine study whose aim was to determine the stress limits of ractopamine saturation in humans. Glover says "Based on how dangerous the study was, the more money you get." References External links Ractopamine page Ractopamine study World Anti-Doping Agency prohibited substances 1999 introductions Food additives Beta1-adrenergic agonists Beta2-adrenergic agonists Eli Lilly and Company brands Pork Phenols Phenylethanolamines Racemic mixtures Agriculture in the United States Agricultural research Biotechnology products Livestock Medicated feed Veterinary drugs Food safety Food and Drug Administration