i've always been curious about wormwood and whether there was anything behind its choice of an illustration by Lucretius other than its bitterness:
First because I teach about great things, and hasten to free the mind from the close bondage of religion, then because on a dark theme I trace verses so full of light, touching all with the muses’ charm. For that too is seen to be not without good reason; for even as healers, when they essay to give loathsome wormwood to children, first touch the rim all round the cup with the sweet golden moisture of honey, so that the unwitting age of children may be beguiled as far as the lips, and meanwhile may drink the bitter draught of wormwood, and though charmed may not be harmed, but rather by such means may be restored and come to health; so now, since this philosophy full often seems too bitter to those who have not tasted it, and the multitude shrinks back away from it, I have desired to set forth to you my reasoning in the sweet-tongued song of the muses, and as though to touch it with the pleasant honey of poetry, if perchance I might avail by such means to keep your mind set upon my verses, while you take in the whole nature of things, and are conscious of your profit.
This does not answer that, but apparently wormwood is something that is still studied for its medicinal properties:
