Antagonistic effects against single lethal doses of Amanita phalloides.

Agents with antagonistic effects against phalloidin or alpha-amanitin were tested in mice against lethal doses of an extract from the whole mushroom Amanita phalloides. The following categories of agents reduced lethality after the extract. First, agents protecting only against phalloidin such as rifampicin, phenylbutazone and antamanide. Second, silymarin and prednisolone which display both antiamatoxic and marked (silymarin) or moderate (prednisolone) anti-phallotoxic acitivty. Thioctic acid displayed some activity when tested against mid-lethal doses of the extract. Cytochrome c, a chemical with curative potencies against alpha-amanitin did not reduce the lethality of the exact. All of the effective agents acted only when applied prior to the poisoning. The pattern or protective activity would indicate that in mice death after single doses of Amanita phalloides may follow a qualitatively particular couse which is difficult to ascribe to phallo- or amatoxic effects alone.