In modern form opodeldoc is a mixture of soap in alcohol, to which camphor and sometimes a number of herbal essences, most notably wormwood, are added.
[1] As to the origin of the name, Kurt Peters speculated that it was coined by Paracelsus from syllables from the words "opoponax, bdellium, and aristolochia."
Opoponax is a variety of myrrh; bdellium is Commiphora wightii, which produces a similar resin; and Aristolochia is a widely distributed genus which includes A. pfeiferi, A. rugosa and A. trilobata that are used in folk medicine to cure snakebites.
Steer" preparation had been successfully imported into the U.S., and was common enough there to rank as one of the eight patent medicines to be analyzed (although not condemned) by the Philadelphia College of Pharmacy in 1824.
Edgar Allan Poe used "Oppodeldoc" as a pseudonym for a character in the short story "The Literary Life of Thingum Bob, Esq.