Studies of scorpion antivenins. 1. Paraspecificity.

This paper describes neutralization tests conducted to determine the effectiveness of five commercially available antivenins, each from a different geographical area, in neutralizing homologous and heterologous scorpion venoms. Venoms of eight scorpion species were used. The work was undertaken because of current interest in the development of polyvalent antivenins for the treatment of venomous bites and stings, and for determination of paraspecific action of existing antivenins as a first step in such a developmental programme. During the studies described, several instances of cross-protection were found, and in some tests heterologous antivenins were more effective than homologous antivenins in protecting white mice against the effects of venom injections. The results obtained should be of practical value in planning a systematic approach towards production of a polyvalent antivenin for use anywhere in the world.