Organophosphate (OP) poisoning continues to represent an important medical issue through its high prevalence among toxic pathologies and through its severity. In diagnosing this toxicological disorder, the most frequently utilized and available laboratory test remains the assessment of plasma cholinesterase - butyrylcholinesterase (BChE) - activity. Despite the reluctance of many researchers on the usefulness of serum BChE for kinetic analysis in OP intoxications, we have tested a recently proposed protocol, which is safe, non-expensive, easy to perform, appropriate to distinguish between an aged cholinesterase and a still reactivable one. Our aim was to validate the usefulness of this protocol, studying a series of 23 consecutive patients acutely intoxicated with OP, admitted in a regional Emergency Hospital, over a 1-year period. Introducing the proposed test in the routine of monitoring OP-intoxicated patients has resulted in the identification of a pattern with a funnel aspect, consequence of the initial possibility to increment the degree of BChE activity. This funnel shape defines the presence of reactivability, while its absence demonstrates the lack of obidoximes effect, due to cholinesterase's ageing process. This method consisted in an advantage for the diagnosis, having the potential of improving prognostic evaluation and therapeutic orientation in OP intoxications.