Foxglove

Botanical and Common Names

Family Scrophulariaceae
Digitalis purpurea (Foxglove, Dead Men’s Bells, Dog’s Finger, Fairy Fingers, Fairy Gloves, Finger Flower, Folks’ Glove, Lion’s Mouth, Ladies’ Glove, Witches’ Gloves, Gloves of Our Lady, Fairy Caps, Fairy Thimbles, Virgin’s Glove)
Digitalis lanata (Wooly Foxglove)
Digitalis lutea (Yellow Foxglove)

Cautions

Excessive doses of the herb are fatal. Use only under professional guidance.

Description

Native to Europe, the plant can now be found throughout the world, growing in woodland areas, on roadsides, and in mountainous regions. The herb is an erect perennial growing to a height of three to five feet, having a single stem, broad lance-shaped leaves, and bell-shaped flowesr in long spikes that can be yellow, purple, or white. Although the wild plants are considered superior, it is cultivated for medicinal purposes. In the US, it is cultivated mainly in New York, Washington, Utah, and Colorado. The leaves are gathered in the second summer of growth.

History

In medical history, foxglove is best known as the discovery of William Withering, an 18th century English country doctor. Curious about the formula of a local herbalist, he explored the plant's potential medical use. His work led to the production of the heart medication we know today.

The drug's use originated in Ireland, then went to Scotland and England before reaching Central Europe. It was originally used to treat ulcers in the lower abdomen, boils, headaches, abscesses, and paralysis, and externally for healing wounds. It was also used for cardiac insufficiency, especially in cases of high blood pressure.

Key Actions

cardiac regulator
diuretic

Key Components

cardiac glycosides (including digoxin, digitoxin, and lanatosides)

Medicinal Parts

Leaves
Besides traces of saponins, the herb also contains powerful diuretic chemicals which have proven useful in the treatment of edema or dropsy.

Traditional Uses

The main action of foxglove is to aid an ailing heart. As heart disease worsens, the heart's ability to maintain normal circulation decreases. The glycosides in this plant slow the rate and enable the heart to beat more strongly and regularly without requiring more oxygen. At the same time, it stimulates urine production, which lowers the volume of blood, lessening the load on the heart.

Today, yellow foxglove is not used much in herbal medicine. The Wooly foxglove is the main source of cardiac glycosides. Wooly foxglove has three times the physiological effect as the common foxglove. However, the common foxglove still has a profound tonic effect on a diseased heart.

In recent years, pharmaceutical manufacturers have tended to abandon D. purpurea in favour of a related species, D. lanata, which grows in Northern Europe and the Middle East. This herb produces the same therapeutic effects, but contains greater amounts of the active principals.