Acute paracetamol poisoning remains very problematic because of its insidious and rapid progression to fulminant hepatitis, even death, in the absence of adequate medical care. The latter depends in particular on the dosage of paracetamolemia that can be carried out by several methods, some of which are time-consuming, expensive or depend on the presence of specific reagents. The present work proposes to validate a plasma paracetamol assay method by UV/visible spectrophotometry applicable for toxicological emergencies, which can be used in laboratories with limited resources.

Analytical optimizations were carried out based on the method of Glynn and Kendal for the determination of paracetamol on plasma by spectrophotometry. The guide of the European Medicines Agency (EMA) was taken as the main reference for the analytical validation of the method.

Good linearity was obtained in the assay range from 40 to 400μg/mL with a correlation coefficient r=0.9941. The accuracy and fidelity obtained fulfilled the requirements of the validation protocol. The detection and quantification limits are respectively 10μg/mL and 40μg/mL. Analysis by the validated method is 20 times cheaper than the enzyme immunoassay method in terms of chemicals and reagents consumed.

The method has been validated according to the requirements of the EMA and can therefore be used routinely. It is a low-cost method and is a good alternative when conventional methods are not available.