@rebecross I knew vaguely that there was something known as "pleurisy root" for treating lungs, but no details, so I decided to look it up.
Here is what I learned. Pleurisy root is one of many names for the plant Asclepias Tuberosa, most commonly known as Butterfly Weed or Butterfly Milkweed.
There appears to be no recent scientific research about either the true efficacy of the plant, and it is unclear the mechanism by which it works. Is is known however, that it can have some fairly severe adverse effects.
The best I could do was to find what is published by WebMD:
https://www.webmd.com/vitamins/ai/ingredientmono-469/pleurisy-root

As with all supplements and natural cures, there is no oversight of purity or dosage, no inspection to be sure you are getting what is labeled on the package. So if you decide to try it, be careful where you buy it.
Sue