Black root or (Leptandra virginica) is a good laxative and internal tonic and is often used in cases of sluggish liver to increase the flow of bile. The fresh root is a violent cathartic and emetic. The dried root is milder and more tolerable.
Black root is also a good tonic for the stomach and in conditions of diarrhea, chronic dysentery, cholera infantum, and torpidity of the liver.
This root is best used with medical supervision as the fresh is too toxic and the dried root requires caution when used. A teaspoon of the chopped root steeped in boiling water for 30 minutes. Drink cold in small amounts before meals and gradually increase dosage not to exceed one cup per day.
Other common names include: Culver’s physic, tall speedwell, tall veronica, Culver’s root, beaumont root, bowman’s root, leptandra, hini, oxadoddy, physic root and whorlywort.