Several classes of chemical compounds are classified under the generic term of "veterinary drugs" and this can be challenging when developing analytical methods.It has also been recognized by regulatory bodies, that there are a lack of appropriate quantitative efficient methods.Here UPLC-MS/MS is investigated for the analysis of some of the more challenging veterinary drugs.This poster addresses some of the challenges associated to the compounds: 1) dexamethasone & betamethasone which are synthetic glucocorticoids used in animal husbandry and also 2) recombinant bovine somatotropin which is a growth hormone used in some countries as a general growth promoter in pigs and cattle but also in lactating cows to increase milk production.These challenges include maintaining chromatographic separation of the epimers in a short time-frame, testing for the presence of protein-based compounds in animal samples, and the detection of both examples at low levels in complex matrices such as liver.