Three simple, accurate, precise, reproducible, requiring no prior separation and economical procedures for simultaneous estimation of losartan potassium and s(-)amlodipine besylate hemipentahydrate in tablet dosage form have been developed. First method employs formation and solving of simultaneous equation using 247 nm and 354 nm as two analytical wavelengths for both drugs in methanol. The second method is Q value analysis based on measurement of absorptivity at 253 nm (as an iso-absorptive point) and 354 nm. losartan potassium and s(- )amlodipine besylate hemipentahydrate at their respective λmax 247 nm and 354 nm and at isoabsorptive point 253 nm shows linearity in a concentration range of 2-20 μg/mL. Third method is first order derivative specrophotometeric analysis based on measurement of absorptivity at 249 nm for s(-)amlodipine besylate hemipentahydrate and 220 nm for losartan potassium with cross point. Recovery studies range from 99.99% for losartan potassium and 99.98% for s(-)amlodipine besylate hemipentahydrate in case of simultaneous equation method and 99.97% for losartan potassium and 100.02% for s(-) amlodipine besylate hemipentahydrate in case of Q - analysis method and 99.98% for Losartan Potassium and 101.01% for s(-)amlodipine besylate hemipentahydrate in case of derivative specrophotometeric method, confirming the accuracy of the proposed method. The proposed methods are recommended for routine analysis since it is rapid, simple, accurate and also sensitive and specific by no heating and no organic solvent extraction.
