Part 6 of 6 of an interview with David Peck, D.O.
Peruvian Bark, Cinchona officinalis
Mütter Museum, College of Physicians, Philadelphia
Illustration from William Woodville's Medical Botany (1793).
Cinchona officinalis, a South American evergreen commonly called Peruvian bark. The dried bark of the stem and root was routinely used in the treatment of all fevers in the 18th and early 19th centuries. It was also used to make a tonic to aid digestion, and as a topical to restore tissue. Lewis mixed it with gunpowder to make a poultice for snakebites, as well as for his own gunshot wound.
On the 4th of July, 1804, Private Joseph Field was bitten on the ankle by what was probably a prairie rattlesnake. Rattlesnakes, interestingly enough, have the ability to vary the amount of venom that they inject into their victims. This bite, for Joseph Field, was probably what we call a minimal envenomation bite. His symptoms were very slight, he probably had some bruising, pain, swelling of the ankle and foot. Lewis treated this with a topical application of Peruvian bark, which was the medicine that was actually effective against the signs of malaria, but probably totally ineffective for the treatment of a rattlesnake bite. But rattlesnake venom contains about five to fifteen different enzymes . . . these long chains of amino acids again. Some of these enzymes actually start to digest the victim. The walls of blood cells are damaged, they start to leak fluid into the tissue which results in swelling of the tissues . . . in Private Field's case the swelling of his foot and ankle. These bites can be very serious. It is entirely possible . . . another case of extremely good luck for the Corps of Discovery . . . that Private Field didn't suffer a severe envenomation, which probably would have resulted in his death on that 4th of July in 1804, in present day Kansas.
The rattlesnake that bit Private Joseph Field was probably a prairie rattlesnake. And when you look at the number of species of rattlesnake that live in the United States presently, the venom potency of that particular rattlesnake probably falls in the mid-range between very potent rattlesnake venom and the least potent rattlesnake venom.
Now, the rattlesnake story comes up again when at Fort Mandan during the winter of 1804-1805. Meriwether Lewis was called to aid in the delivery of a baby, the son of Sacagawea. When Lewis arrived at the delivery he probably wasn't entirely sure of what to do because she was having a difficult delivery.
One of the French fur trappers in the area suggested a folk remedy that he said he had never seen fail to bring about the desired effect. Two rings of the rattlesnake rattle were broken up and given to Sacagawea with some water, and within ten minutes she delivered her baby boy, Jean Baptiste. That is a great story, but I don't think that the rattlesnake rattle had anything to do with the stimulation of the uterus to contract, because rattlesnake rattles are made out of keratin,9 and there is nothing there that that would produce smooth muscle contraction.
The treatment that Meriwether Lewis employed for this rattlesnake bite with Private Field is very interesting . . . the topical application of Peruvian bark. Peruvian bark originally came to Europe about two hundred years prior to this, with the discovery by a Jesuit missionary in South America that the bark was effective against malaria. It actually contains quinine, which is effective against malaria; it's not effective against rattlesnake bites. Modern day treatment for rattlesnake bites is produced by administering the victim what we call antivenin. This is a series of antibody shots that are administered to the victim, and these antibodies will interact with the enzymes that are active in the rattlesnake venom in terms of producing the illness symptoms: the oral numbness, the tongue tingling, the pain and the swelling and other severe signs and symptoms produced by rattlesnake venom.
9. Keratin is the insoluble protein substance of which hair, nails, horns and hooves—as well as rattlesnake rattles—are made.
Supported in part by a grant from the National Park Service, Challenge Cost-Share Program