Abstract
Hypericum perforatum L. (St. John’s wort) is a five-petalled, yellow-flowered perennial weed common to the western United States, Europe, and Asia.1 Close examination of the flowers reveals small black dots that, when rubbed between the fingers, produce a red stain. This red pigment contains the constituent hypericin. Held up to light, the leaves of the plant display a number of bright, translucent dots. This perforated look led to the species name perforatum. The plant is currently cultivated in Europe, North and South America, Australia, and China.2 The aerial parts of the plant are harvested during the flowering season and used in modern, standardized extracts. Dioscorides, the foremost physician of ancient Greece, as well as Pliny and Hippocrates, recommended the herb for a host of ailments including sciatica and poisonous bites. The name St. John’s wort has its origin in Christian folk tradition. St. John’s wort has a long history of use in traditional European herbal medicine. It was, and continues to be, used as a topical treatment for wounds and burns. It has also been used as a folk remedy for kidney, stomach, and lung ailments, and was first noted as a remedy for melancholy and madness by Culpeper in 1652.3