Potassium chloride and potassium bicarbonate effervescent tablets are used to prevent low levels of potassium in blood [1]. Using the monographs from the United States Pharmacopeia and National Formulary (USP-NF) allows pharmaceutical manufacturers and labs to fulfill strict quality regulations for drugs and formulations.

The USP has embarked on a global initiative to modernize many existing monographs. The monograph «Potassium Bicarbonate and Potassium Chloride Effervescent Tablets for Oral Solution» comprises different methods to determine potassium, sodium, but also chloride in these tablets [2]. Ion chromatography (IC) with suppressed conductivity detection has been approved by the USP as a validated method to quantify chloride content in potassium bicarbonate and potassium chloride effervescent tablets for oral suspension [2]. The Metrosep A Supp 16 - 100/4.0 (L91) column provides the required separation of chloride. The method is validated according to USP General Chapter <621> Chromatography, system suitability [3].