An Antimony pill is a pill made from metallic antimony. It was a popular remedy in the nineteenth century, and it was used to purge and revitalise the bowels. In use, it is swallowed and allowed to pass through the body, after which it is customarily recovered for reuse, giving rise to the name everlasting pill.
According to the Medico-Pharmaceutical Critic and Guide (1907), edited by William J. Robinson:
We have referred in the past to the economy which used to be practiced by our fore-fathers. Thus, for instance, it was customary to use leeches over and over again and there are instances of infection with syphilis by leeches that had been previously used on luetic patients. But we believe that the everlasting cathartic pill beats everything in the line of economy. This pill was a little bullet composed of metallic antimony which had or was believed to have the property of purging as often as it was swallowed. It is not inconceivable that it might have had such property, for it is possible that a minute amount was dissolved by the gastro-intestinal juices and this amount, plus the suggestion, was sufficient to produce cathartic action. Then again the everlasting pill probably aided peristalsis by its mechanical weight and motion. The bullet was passed out, recovered from the feces and used over and over again. This, as Dr. J. A. Paris says, was economy in right earnest, for a single pill would serve a whole family during their lives and might be transmitted as an heirloom to posterity.[1]
The "everlasting antimony pill" is mentioned by Stephen Maturin in the novel The Ionian Mission by Patrick O'Brian.
"Pray, Dr Maturin," he said on the quarterdeck, "what is the effect of antimony?""It is a diaphoretic, an expectorant and a moderate cholegogue; but we use it chiefly as an emetic. You have heard of the everlasting antimony pill, sure?"
"Not I."
"It is one of the most economical forms of physic known to man, since a single pill of the metal will serve a numerous household, being ingested, rejected, and so recovered. I have known one handed down for generations... the name is said to signify a monk's bane."
"So I have always understood," said Jack. "But what I really meant was its effect on guns, was a little mixed with the powder."
"Alas, I am wholly ignorant of these things. But if we may go by analogy, it should cause the piece to vomit forth the ball with more than common force."[2]