High performance liquid chromatographic determination of paracetamol in human serum

A method has been developed for the determination of acetaminophen in human serum. Samples are extracted with ethyl acetate. Beta-hydroxyethyl theophylline is used as internal standard. The solvent is evaporated under nitrogen and the residue is analyzed by high-performance liquid chromatography on Lichrosorb RP 18. Extraction efficiency, linearity and assay precision have been determined. The method is rapid and can be easily applied to determine the plasma level of patient having taken overdose of paracetamol.