Abstract
BACKGROUND: Irbesartan and hydrochlorothiazide are a group of anti-hypertensive drugs that are very effective and safe to use to reduce blood pressure and oedema. The combination has a small active ingredient content so that if the treatment didn't meet the requirements for therapeutic doses, it not achieved to the maximum therapy. AIM: The research aims to the simultaneous determination of irbesartan and hydrochlorothiazide in tablets by Ratio subtraction spectrophotometry method. METHODS: The absorption spectra and sample measurement in the Ratio subtraction method performed on Irbesartan at a wavelength of 247.6 nm and 273.6 nm for the Hydrochlorothiazide (HCT) using 0.1 N NaOH as a solution. This method is validated with linearity, accuracy, and precision in intraday and interday, LOD and LOQ and applied in the determination of a mixture of irbesartan and hydrochlorothiazide in the dosage tablet. RESULTS: The validation test for IRB is 101.03 for accuracy, with a precision of 0.57; with precision testing at intraday 0.34 and interday 1.34, and LOD is 0.70 and LOQ is 2.12. Meanwhile, validation for HCT that the accuracy 100.34%; precision 0.89 and precision on intraday 1.20 and interday 1.18, and LOD 0.78 and LOQ 2.37 with IRB levels are 101.03 ± 0.63% and HCT is 100.59 ± 0.91%. CONCLUSION: The ultraviolet spectrophotometric method in subtraction ratio method was validated a method of linearity, accuracy, precision in intraday and interday, LOD, and LOQ and according to ICH guidelines and successfully applied for the determination simultaneous of irbesartan and hydrochlorothiazide in the tablet's dosage form.