To develop and validate simple and rapid isocratic reversed-phase high-performance liquid chromatography method (RP-HPLC) for the simultaneous estimation of Amlodipine , Chlorthalidone and Olmesartan in synthetic mixture. The chromatographic separation was achieved by using mobile phase Methanol and Phosphate Buffer adjusted with Sodium Hydroxide (pH 5) (80:20 v/v), Hypersil BDS C18 column (250 mm x 4.6 mm, 5 ?m particle size). The mobile phase was pumped at a flow rate of 1.0ml/min and the eluents were monitored at 238nm. Retention times were 5.503 min, 3.107 min and 3.980 min for Amlodipine , Chlorthalidone and Olmesartan respectively. Linearity was observed in the concentration range of 2.5-7.5 ?g/ml, 6.25-18.75 ?g/ml and 10-30 ?g/ml for Amlodipine , Chlorthalidone and Olmesartan respectively. The percentage recoveries found to be as for Amlodipine 98.03-101.22 %, Chlorthalidone 98.97-101.38 % and Olmesartan 98.37-101.76 respectively. All the parameters are validated as per ICH guidelines for the method validation and found to be suitable for routine quantitative analysis in pharmaceutical dosage forms.
