Many of these "remedies" and "medicines" are now used as Rx drugs - such as digitalis, which was derived from hawthorn berry, an herb commonly taken for the heart. There are many books written about the scientific validation of herbal medicine. Honey is now the choice for coughs, instead of cough medicine, as well as for wounds (http://www.manukahoneyusa.com/BurnsWoundsUlcersSores.htm). Olive oil is once again suggested for earaches. I also think a cousin to these types of "cures" is nutrition, "Let your food be your medicine and your medicine be your food." as Hippocrates (the Father of Medicine) was know to say.
You might find these books interesting to read:
Traditional Foods Are Your Best Medicine Improving Health and Longevity with Native Nutrition - by Ronald F. Schmid, N.D
Nourishing Traditions - by Sally Fallon
~Gingerbread