Toxicological evaluation of two recently reported treatment protocols
for cyanide-SN (sodium nitrite) + DMAP (4-dimethylaminophenol) and SN
+ HA (hydroxylamine)-was carried out in male rats. Both treatments pro
duced transient hyperammonaemia and decreased mean arterial pressure.
Heart rate decreased and respiratory rate increased, but these changes
reached the level of significance only after SN + HA. Histopathologic
al lesions in lung, liver (SN + HA) and kidney (SN + DMAP) were predom
inantly in the vicinity of blood vessels. The results indicate toxic e
ffects in both treatment groups at a dose known to induce methaemoglob
in concentration to the level of antidotal efficiency in cyanide intox
ication.