Evaluation of the neutralizing ability of antivenom has been traditionally assessed by studying neutralization of lethality (WHO, 1981). However, most venoms are complex secretions that induce a wide variety of pharmacological and pathological effects. Thus, an adequate evaluation of antivenoms must include not only neutralization of lethality, but also neutralization of other relevant effects. In the case of viperine and crotaline snake venoms, it is necessary to evaluate neutralization of lethal, hemorrhagic, defibrinating, coagulant, myotoxic, hypotensive, nephrotoxic and edema-forming effects.
Several groups of investigators have addressed this problem in recent years, and a more comprehensive view of the neutralizing potential of antivenoms is being developed. However, these studies have used highly different methodologies and experimental strategies, thereby making the comparison and evaluation of results difficult, Due to the urgent need to standardize a methodology to test the neutralizing ability of antivenoms, we would like to propose some basic principles to be used.