Objective To study and compare the variations of the Qingkailing injection prepared with the new procedure with injection
prepared with the original procedure. And inspect the reliability of Qingkailing injection by determining pyrogen. Methods in vitro antibacterial assay, fever in rats induced by dried yeast, leucocyte aggregation in bursa of rats induced by CMC-Na, swelling of auricle in mice induced by dimethylbenzene, and competence of clearing up carbon in mice were conducted to investigate the effect of new procedure on the bacteriostatic and antibiotic activities, anti-inflammatory and antipyretic efficacies, and effects on the cytophagocytosis of mononuclear phagocyte system. Results Compared with the injection prepared with original procedures, Qingkailing injection prepared with new procedure is similar in antipyretic, anti-inflammatory effects, and the difference has no statistical significance. The antibiotic and bacteriostatic activity of the injection prepared with the new procedure is slightly stronger than that prepared with the original procedure. The injection prepared with new procedures has obvious inhibitory effect on cell migration in metaphase of inflammation induced by CMC-Na in rats. The qualification rate of injection prepared with the new procedures is markedly higher than that prepared with the original procedure. Conclusions The injection prepared with the new procedure surpasses the injection prepared with the original procedure in antibacterial and anti-inflammatory actions, and similar with each other in other characters with no statistical significance. And the reduction of pyrogen in injection prepared with new procedure will enormously decrease the incidence of adverse reactions.