OBJECTIVETo evaluate the sensitization effect of polysorbate 80 and polysorbate 80 contained Houttuynia cordata Injection in different concentrations on Beagle.

METHODSBeagles, a kind of animal highly sensitive to sensitizing agents, were randomly divided into 18 groups, 3 in each group. They received respectively the intravenous infusion of polysorbate 80 made by different factories in different concentrations (0.25%, 0.10%, 0.05%), and Houttuynia cordata Injection containing polysorbate 80 in concentration of 0.25% or 0.30%, with the constant infusing speed of 5 mL/min and volume of 10 mL/kg. Changes of animals' condition were observed before infusion and in the 24 h after infusion, time of symptom appearance and disappearance was recorded, and the grade of response was determined. Moreover, blood samples of animals were collected before infusion and 10 min after ending infusion for measuring histamine content in plasma using ELISA. Then the sensitization effect was comprehensively estimated by combined consideration of the responding grade and histamine level.

RESULTSNo typical symptom of anaphylactoid reaction and over 1-fold increase of histamine level was found in all groups that received intravenous infusion of polysorbate 80 or polysorbate 80 contained Houttuynia cordata Injection in different concentrations. Estimation showed that all test solutions didn't induce typical anaphylactoid reaction on Beagle.

CONCLUSIONSConsidering both the appearance of symptoms and the elevation of blood content of histamine could be taken as the criteria for comprehensive diagnosis of anaphylactoid reactions. The solubilization effect and safety (for foreclose anaphylactoid reaction) of polysorbate 80 could be ensured by controlling its quality and concentration below 0.25% or 0.30%.