Quantitation of Cephalexin in Pharmaceutical Dosage Forms Using High-Performance Liquid Chromatography

A high-performance liquid chromatography method has been developed to quantify cephalexin in pharmaceutical dosage forms, capsules, pediatric drops and suspensions. The method is accurate and precise with a percent relative standard deviation of 0.8 based on 6 readings. There is no interference from a variety of excipients present in the dosage forms. The procedure for the extraction of cephalexin from the dosage forms is very simple. The method is stability indicating since a sample decomposed using sodium hydroxide showed very little potency and new peaks in the chromatogram. In the powder form cephalexin appears to be very stable.