Abstract
The H-point standard addition method was used for the simultaneous spectrophotometric determination of captopril and hydrochlorothiazide in pharmaceutical formulations, absorbances in wavelength pairs λ 211.5 and λ 230.3 nm, were monitored with the addition of standard captopril solutions. Captopril and hydrochlorothiazide concentration ratios are estimated to be 1.0:0.8 and 2.5:15,recovery at 95.33% - 104.37% and 96.8% - 105% respectively, with a precision of up to 2.The method was successfully used to evaluate the antihypertensive captopril drug in a binary combination of hydrochlorothiazide in real samples with high precision and accuracy within the recovery percentage.