Ibuprofen and carbamazepine caused a moderate inhibition (28–40% compared to controls) on CE activity of D. labrax, A. rostratus and C. laticeps (Fig. 2), whereas diclofenac significantly inhibited CE activity only in A. rostratus 65% of controls, and acetaminophen did not change CE activity. In human pharmacology, the role of CEs in the hydrolysis of NSAID drugs has great concern in cancer research. Moreover, many NSAIDs containing carboxylic groups are metabolized via acyl glucuronide formation. Some of these glucuronide-derivate metabolites are, in turn, CE inhibitors, being of great concern in drug–drug interactions. Comparison with literature data was not feasible because of the scarce number of Eco toxicological investigations dealing with pharmaceutical metabolism in non-mammals