
Herbal medicine, often taken in the form of supplements, is a part of all whole medicine systems. Whole medical systems are complete medical systems, like traditional Chinese medicine (TCM) or naturopathy, that where developed totally independant from allopathic (western conventional) medicine. In conventional medicine, many pharmaceuticals are derived from herbs, plants you may be familiar with.
Digitalis a heart drug, is from the foxglove plant. Morphine is from the opium poppy. Daffodil bulbs are used to make galantamine a drug for alzheimer's. Indian snakeroot plant is utilized in making reserpine, a drug to reduce blood pressure. A cancer drug called vincristine is from the rosy periwinkle plant. And a common one that you may already be aware of is asprin, it comes from the willow tree.
Herbal medicine comes in many forms. Every medicine has componants derived from nature. If they are synthetic (produced in a lab) it means that us humans have learned to replicate something that we found in nature.