Lewis and Clark expedition left a trail of heavy-metal laxatives
Dozens and dozens of mercury-laden purgative pills invented by Founding Father Benjamin Rush were an indispensible part of the Corps of Discovery's kit; the toxic-but-effective tablets helped explorers cope with a very-low-fiber diet.
This photograph, from the state of Oregon's official Web site at www.
oregon.gov, shows the reproduction of Fort Clatsop, built at or near the
site of the Corps of Expedition's original buildings. Dr. Rush's Bilious Pills
have not been particularly helpful in locating the original Fort Clatsop,
long since rotted away -- probably because the men preferred to do their
"thunderclapping" at a distance from the fort itself. Click here to see a
By Finn J.D. John — June 29, 2010
As Lewis and Clark’s Corps of Discovery worked its way across North America to Oregon’s Fort Clatsop, it left something behind that would prove invaluable to future historians:
This sounds trivial today, but at the time laxatives (or, rather, purgatives in general) were a big deal. The Corps left on its journey long before anyone knew what a microbe was, and physicians knew almost nothing about how the human body worked. What they had was a basic theory, which had come down to them from about 150 A.D., courtesy of a Roman doctor named Galen. The idea was that illness was caused by an imbalance in the body’s “humors,” or fluids – blood, phlegm, yellow bile and black bile. Too much blood caused problems like fevers; the answer was to let a pint or two of blood out of the patient. And too much bile caused problems like constipation; the answer was to give the patient a powerful laxative or emetic to cause frenetic purging, from one end or the other.
The wonder drug that works wonders
By the time of the American revolution, a substance called “calomel” was the laxative of choice.
This recipe for a milder version of Rush's Bilious Pills
comes from the National Formulary in 1945. This
image appears in the Lewis and Clark Fort Mandan
Foundation's Web site, at which there's a lot more
information about the ingredients in this compound.
Mercury was still being used as an internal medicine
in the 1960s and as a topical antiseptic (chiefly as
Mercurochrome) into the 1990s.
Calomel was the wonder drug of the age. In large doses, it functioned as a savage purgative, causing lengthy and productive sessions in the outhouse, guaranteeing the restoration of one’s bile balance. And in small doses, it was effective against the most dreaded “social disease” of the age, syphilis.
But take too much of it and your teeth would fall out, and you might die of mercury poisoning. Calomel’s modern scientific name is mercury chloride.
When the Corps of Discovery left the East Coast, Lewis and Clark brought with them several pounds of mercury chloride – in the form of dozens and dozens of beefy white tablets labeled “Dr. Rush’s Bilious Pills.” These pills were almost 50 percent calomel – and they were big pills, at least four times the size of an aspirin tablet.
Founding father, physician, laxative-maker
The pills’ inventor, Dr. Benjamin Rush, was America’s most prominent colonial physician, a signer of the Declaration of Independence and a personal friend of then-President Thomas Jefferson. His star had fallen considerably after the “heroic” style of medicine he favored, featuring heavy purging and copious bloodletting, had a noticeably bad effect on his patients’ survival rate during a yellow fever epidemic in Philadelphia in 1793. But he was still an important man.
On the trail, the pills quickly became a critical part of the Corps of Discovery’s kit. More than a few of the men did end up needing treatment for syphilis, either for pre-existing problems or for ones picked up along the way from friendly Native American women. But almost everyone needed a laxative. Week after week, hunting parties went out and brought back animals to eat. The explorers lived on almost nothing but meat. This low-fiber diet had predictable results.
Enter Dr. Rush’s Bilious Pills. The men called these “Thunder Clappers.” They were extraordinarily effective.
And they’ve proven effective for later generations as well. Calomel, as it turns out, is only slightly soluble in human digestion, and much of it goes out with the resulting “purge.” Once in the earth, it lasts virtually forever without dissolving or breaking down.
So as Lewis and Clark’s men made their way across the continent and across Oregon, they were unknowingly depositing a trail of heavy metals along the way – a trail that historians and scientists have been able to detect and use to document almost their every movement, so to speak.
(Sources: Prof. James Mohr class lecture, History of American Medicine, October 2009, Univ. of Oregon; Nondorf, Tracy. “Lewis and Clark: Doctors in the Wilderness” (research paper), 2004, Washington University; www.nps.gov)