Ability of six Latin American antivenoms to neutralize the venom of mapaná equis (Bothrops atrox) from Antioquia and Chocó (Colombia).

This investigation compared the ability of six Latin American antivenoms (monovalent antibothropic INS, Santafé de Bogotá; polyvalent INS; polyvalent probiol, Santafé de Bogotá; antibothropic Instituto Butantan, IB, São Paulo, Brazil; polyvalent Instituto Clodomiro Picado, ICP, San José, Costa Rica; polyvalent MYN, Mexico) to neutralize various pharmacological and enzymatic effects of Bothrops atrox venom from Antioquia and Chocó, north-west of Colombia. Our results demonstrated conspicuous differences in the ability of the six antivenoms. In terms of neutralization of lethality, the highest efficacy was observed in the polyvalent INS and the lowest in the polyvalent MYN antivenom. All antivenoms were highly effective in the neutralization of hemorrhage, polyvalent INS and probiol being the highest. In the neutralization of edema-forming activity, the most effective antivenom was the polyvalent (ICP); monovalent (INS) and polyvalent (MYN) were the least effective. All antivenoms were effective in the neutralization of the myotoxic activity of B. atrox venom, the most effective being the polyvalent (INS) and antibothropic (IB). Defibrinating activity was neutralized by all antivenoms; polyvalent (MYN) showed the lowest efficiency. Polyvalent (ICP) antivenom had the highest neutralizing ability against the indirect hemolytic effect of B. atrox venom; polyvalent (MYN) did not neutralize this enzymatic activity. Overall, the polyvalent antivenom (INS) showed the highest neutralizing ability.