[Admixtures present in antitoxic horse sera and pepsin preparations].

Antitoxic therapeutic sera produced by the method "Diaferm-3" (devised at the Institute of Epidemiology and Microbiology of the USSR Academy of Medical Sciences) are contaminated in the process of production with group-specific substances and extraneous enzymes contained in crude preparations of swine pepsin. These ballast substances have a negative influence on the process of purification and the stability of antitoxin during the storage of the sera and constitute one of the reasons of their high reactogenicity.