The 4th Meeting of Experts in Animal Envenoming was held in Mexico city in 2000.

From Serotherapy to Fabotherapy

Paniagua-Solís, Jorge F.(1,2); Mancilla, Rita(1); González, Carlos(3) and Alagón, Alejandro(3)

(1)Instituto Bioclon, S.A. de C.V., (2)Laboratorios Silanes, S.A. de C.V., (3)Instituto de Biotecnología-UNAM, México, D.F.

ABSTRACT: The main problem when treating animal envenomings is the incidence of secondary reactions following the administration of first-generation raw serums or antidotes. The incidence and seriousness of secondary hypersensitivity effects were seen to diminish with the fractionation of G immunoglobulins (IgG) by precipitation with different salts. This procedure allowed immunoglobulins to be separated from other serum proteins, such as albumin, in order to obtain the so-called second-generation serums. F(ab)2 immunoglobulin portions proved to be the part of immunoglobulin that neutralizes and interacts with toxins and venoms; these make up the third-generation serums. Today, several experts suggest the terms FABOTHERAPY and FABOTHERAPIC to replace Serotherapy and Antiserum when working with antivenoms made up of purified immunoglobulin F(ab)2 fragments treated with proteolytic digestion. These changes in terminology will help to eliminate the prevailing idea in the medical community that the use of antiserums is not safe, poorly tolerated, and may even lead to death due to their unwanted effects. Today, FABOTHERAPY has been proven to have high neutralizing venom specificity and to lack the adverse reactions of the first and second-generation serums. Four products are available as Fabotherapic anti-scorpion, anti-snake, anti-coral, and anti-spider (black widow) antivenoms. All these products contain 80'% F(ab) fragments, less than 10% Fab, 5% low molecular weight components, and NO Albumin. These have been widely used in Mexico for a long time.