Antipoison

In venemous natures something may be amiable: poisons afford antipoisons: nothing is totally, or altogether uselessly bad.

1849, Golding Bird, “Lectures on Materia Medica,” Lecture III, “The Materia Medica of the 17th Century” in Medical Times, Volume 19, 2 June, 1849, p. 617, In consideration of the high value attached to some of the bezoars, it was very common for them to be adulterated—some good—some bad imitations,—for instance, the goa antipoison, the prescription for which in the first Pharmacopœia was—Hyacinth, jasper, sapphire, and topaz.