Phenol used as a preservative in Bothrops antivenom induces impairment in leukocyte-endothelial interactions

The effect of Bothrops antivenom on blocking the disturbances induced by Bothrops jararaca venom in leukocyte-endothelial interactions (LEI) at the microcirculation of the cremaster muscle in mice was evaluated using intravital microscopy. Our findings showed that an i.v. injection of Bothrops antivenom, per se, induced changes in LEI, similar to those induced by an s.c. injection of B. jararaca venom, and that Bothrops antivenom can also induce ephemeral symptoms, such as tremor and dyspnea in mice. These effects were mostly due to phenol used in Bothrops antivenom as a preservative, since animals injected i.v. with a phenol solution, but not with phenol-free Bothrops antivenom, presented those effects on LEI, and also tremor and dyspnea. In addition, phenol-free antivenom abrogated venom-induced changes in LEI parameters. The present data demonstrate that Bothrops antivenom contains antibodies that neutralize toxins of B. jararaca venom that impair LEI, and suggest that the phenol used as a preservative in it can originate some undesired effects.