Antagonism of cyanide intoxication with sodium pyruvate

Cyanide intoxication in mice can be effectively antagonized by sodium pyruvate, particularly if it is administered in combination with the antidotes, sodium nitrite and sodium thiosulfate. Potency ratios derived from the LD50 data were compared in groups of mice treated with sodium nitrite, sodium thiosulfate, and sodium pyruvate either alone or in various combinations. These results indicate that the administration of sodium pyruvate alone does provide minimal, but statistically significant, protection against the lethal effects of cyanide. Sodium pyruvate does not enhance the effect of sodium nitrite; however, it does potentiate the antidotal effect of sodium thiosulfate. The sodium thiosulfate and sodium pyruvate combination is not as effective as the sodium nitrite and sodium thiosulfate combination, but the addition of sodium pyruvate to the sodium nitrite-sodium thiosulfate combination further enhances the antidotal effect. No further enhancement is observed when sodium nitrite, sodium thiosulfate, and sodium pyruvate are combined with oxygen.