The pyrogenic activity of 10% inulin injections prepared at a hospital pharmacy was measured using the Pyrogen test in Japanese Pharmacopeia (JP), while the endotoxin concentration in the injections was determined by the, Limulus test, which were JP Endotoxin test and a turbidmetric kinetic assay. After the intravenous administration of 30 ml of inulin injections to a rabbit, the rectal temperature rose to 1.5° compared with that before administration. As a result, the endotoxin was found in all lots of the inulin injections tested, and their values were markedly beyond the limit of Water For Injections prescribed in JP (0.25 EU/ml). In addition, the endotoxin content varied between the various lots of inulin powder, and also between the manufacturers. The endotoxin in inulin injection was removed (less than the quantitative limit of 0.031 EU/ml) by adding activated carbon black to the injection or the filtration using a Posidyne® Nylon 66 filter. No pyrogenic activity was observed in the inulin injections after the removal of endotoxin.
Based on these results, the adverse effects induced by inulin injections may thus be caused by endotoxin derived from inulin. This method using either adsorption or filtration is thus considered to be useful for the removal of endotoxin when preparing inulin injections.
