Have you seen ads for a nutritional supplement designed to improve brain function which contains the ingredient bacopa monnieri? Known in Ayurvedic circles as Brahmi, this plant is familiar to aquarium hobbyists, as it is an easy to grow ornamental that makes a nice habitat for fish. Sold under the name Water Hyssop, the antioxidant bacopa monnieri plant is believed to promote brain function and memory, encourage liver function, protect against hypoglycemia, normalize blood pressure, calm and improve sleep, and nourish hair, among its benefits. Although moderation is advised for all nutritional supplements, there are not believed to be any harmful side effects to the ingestion of any part of this plant.
Water hyssop can be purchased in pet stores that sell aquatic plants. It is also available online. I bought mine from an excellent Amazon vendor called Exotic Plants. It was inexpensive, shipped fast, and the cuttings were very healthy and well packaged. To propagate it, just cut the stem and it will form new roots in days immersed in clean (preferably purified) water. After the first roots form, add a drop or two of liquid plant food now and then.