The stability of amoxycillin sodium in intravenous infusion fluids

The stability of amoxycillin sodium has been determined at 25 degrees C in water and in ten intravenous infusion fluids at concentrations of 1, 2 and 5% w/v. Little difference in stability was found between 1% and 2% amoxycillin solutions in the various vehicles, but the antibiotic was significantly less stable at 5%. Stabilities in sodium and potassium chloride solutions were similar to those in water and were markedly superior to those in dextrose or dextran fluids. Solutions in lactate or bicarbonate had intermediate stability. The antibiotic was, for practical purposes, unstable in 30% sorbitol solution. Guidelines are provided for intravenous infusion of amoxycillin in the solutions studied.