Treatment of experimental poisoning produced by extracts of Amanita phalloides

Abstract

Agents known to antagonize in mice the lethal effects of phalloidin or α-amanitin, two major toxins of the deathcap, Amanita phalloides, were tested against lethal doses of the whole extract from the mushroom. The extract was given in fractionated doses that produced death in a temporal pattern similar to the one seen clinically or after α-amanitin. No activity against the extract was provided by drugs with prophylactic properties against phalloidin such as rifampicin and phenylbutazone. Cytochrome c, an agent with curative properties against α-amanitin, was also ineffective. However, prednisolone and silymarin as antidotes increased markedly the survival after the extract. Similarly, only these two agents protected mice against poisoning by α-amanitin. The efficacy of prednisolone and silymarin against the extract may thus be due to their capacity to prevent the toxicity of amatoxins. The latter are thought to be responsible for the fatalities in clinical intoxications, and they are presumed to be continuously reabsorbed because of enterohepatic recirculation. It is suggested that the fatalities after single lethal doses of the mushroom extract were caused predominantly by phallotoxins, whereas with fractionated administration of the extract, the fatalities may be due mainly to amatoxic effects.