14. Medical Treatments on the Lewis and Clark Expedition

Portrait of Dr. Benjamin Rush by Charles Willson Peale. (Image courtesy of Independence National Historical Park)

The journey of the Corps of Discovery covered nearly 8,000 acres of unknown perils and landscapes. Surprisingly, none of the members on the mission included a trained doctor. President Jerfferson was weary of colonial medicine and believed that it was based on theory rather than hard science. This distrust of physicians led Jefferson to appoint Meriwether Lewis as the primary medical physician of the Corps. 


Lewis had prior medical knowledge from his mother, Lucy, who was a noted herbalist. Jefferson required Lewis to receive supplementary medical training from Benjamin Rush, America’s premiere physician. Lewis learned typical medical theory and practice. One of his major duties on the mission included the health and care of his soldiers.


Some of medicines and medical equipment Lewis brought on the journey included:

  • Rush’s Pills: Created by Benjamin Rush, these were used as a  “cure-all” and were liberally given. They were also known as “Thunder-clappers” for the laxative’s sudden effects.
  • Lancets - to make punctures
  • Forceps - to grasp small objects
  • Syringes - to dispense medicines
  • Laudanum - used to temporary alleviate coughing, diarrhea and pain
  • Cream Of Tartar - a mild laxative
  • Elixir Of Vitriol - typically mixed with other ingredients such as ginger, it was used as a tonic for stomach disorders
  • Magnesia - antacid
  • Mercury - the standard treatment of the time for syphilis


For a full list of medicines ordered for the journey, please visit: http://www.lewis-clark.org/article/2562

To make his “Thunder Clappers,” Dr. Benjamin Rush concocted a mixture of calomel, chlorine, jalap and additional mercury to create a proprietary purgative. (Image courtesy of FreeMercuryKids.org)

Rush submitted to Lewis ten health commandments to subscribe to for the Corps of Discovery: 


  1. Flannel worn next to the skin, especially in wet weather.
  2. Always to take a little raw spirits after being very wet or much fatigued; and as little as possible at any other time.
  3. When you feel the least indisposition, fasting and rest; and diluting drinks for a few hours, take a sweat, and if costive take a purge of two pills every four hours until they operate freely.
  4. Unusual costiveness is often the sign of an approaching disease. When you feel it, take one or two of the opening pills.
  5. Where salt cannot be had with your meat, steep it a day or two in common lye.
  6. In difficult and laborious enterprises or marches, eating sparingly will enable you to bear them with less fatigue and more safety to your health.
  7. Washing feet with spirit when chilled, and every morning with cold water.
  8. Molasses or sugar with water with vit. [victuals] and for drink with meals.
  9. Shoes without heels.
  10. Lying down when fatigued.


Online exhibit on the medicines of the Corps of Discovery: http://exhibits.hsl.virginia.edu/lewisclark/medicine/