Three different and complementary chromatographic methods are described for quantitative determination of albendazole (ABZ) and its two main metabolites: albendazole sulphoxide (SOABZ) and albendazole sulphone (SO2ABZ). ABZ, SOABZ and SO2ABZ can be quantified by two RP-HPLC methods with an ODS2 column and two different mobile phases. One of methanol-water (60:40) for ABZ and a second one of phosphoric acid in water-acetonitrile (80:20) for SOABZ and SO2ABZ. SOABZ bears an asymmetric sulphur centre. Quantitative assay of (+) SOABZ and (-) SOABZ can be performed by HPLC. A chiral AGP column and a mobile phase of sodium phosphate buffer (8 mM, pH 7.0) containing different amounts of 2-propanol between 0 to 2% were used. Pharmacokinetic characteristics of ABZ following oral administration of a liquid formulation of ABZ (12 mg/kg) in mice has been studied with these three complementary HPLC methods and the results are reported.